aboutsummaryrefslogtreecommitdiff
path: root/xorg-server/dix/ptrveloc.c
diff options
context:
space:
mode:
Diffstat (limited to 'xorg-server/dix/ptrveloc.c')
-rw-r--r--xorg-server/dix/ptrveloc.c2372
1 files changed, 1197 insertions, 1175 deletions
diff --git a/xorg-server/dix/ptrveloc.c b/xorg-server/dix/ptrveloc.c
index 9a8737cf4..e6ac2ed14 100644
--- a/xorg-server/dix/ptrveloc.c
+++ b/xorg-server/dix/ptrveloc.c
@@ -1,1175 +1,1197 @@
-/*
- *
- * Copyright © 2006-2009 Simon Thum simon dot thum at gmx dot de
- *
- * Permission is hereby granted, free of charge, to any person obtaining a
- * copy of this software and associated documentation files (the "Software"),
- * to deal in the Software without restriction, including without limitation
- * the rights to use, copy, modify, merge, publish, distribute, sublicense,
- * and/or sell copies of the Software, and to permit persons to whom the
- * Software is furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice (including the next
- * paragraph) shall be included in all copies or substantial portions of the
- * Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
- * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
- * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
- * DEALINGS IN THE SOFTWARE.
- */
-
-#ifdef HAVE_DIX_CONFIG_H
-#include <dix-config.h>
-#endif
-
-#include <math.h>
-#include <ptrveloc.h>
-#include <exevents.h>
-#include <X11/Xatom.h>
-
-#include <xserver-properties.h>
-
-/*****************************************************************************
- * Predictable pointer acceleration
- *
- * 2006-2009 by Simon Thum (simon [dot] thum [at] gmx de)
- *
- * Serves 3 complementary functions:
- * 1) provide a sophisticated ballistic velocity estimate to improve
- * the relation between velocity (of the device) and acceleration
- * 2) make arbitrary acceleration profiles possible
- * 3) decelerate by two means (constant and adaptive) if enabled
- *
- * Important concepts are the
- *
- * - Scheme
- * which selects the basic algorithm
- * (see devices.c/InitPointerAccelerationScheme)
- * - Profile
- * which returns an acceleration
- * for a given velocity
- *
- * The profile can be selected by the user at runtime.
- * The classic profile is intended to cleanly perform old-style
- * function selection (threshold =/!= 0)
- *
- ****************************************************************************/
-
-/* fwds */
-int
-SetAccelerationProfile(DeviceVelocityPtr vel, int profile_num);
-static float
-SimpleSmoothProfile(DeviceIntPtr dev, DeviceVelocityPtr vel, float velocity,
- float threshold, float acc);
-static PointerAccelerationProfileFunc
-GetAccelerationProfile(DeviceVelocityPtr vel, int profile_num);
-
-/*#define PTRACCEL_DEBUGGING*/
-
-#ifdef PTRACCEL_DEBUGGING
-#define DebugAccelF ErrorF
-#else
-#define DebugAccelF(...) /* */
-#endif
-
-/********************************
- * Init/Uninit
- *******************************/
-
-/* some int which is not a profile number */
-#define PROFILE_UNINITIALIZE (-100)
-
-
-/**
- * Init struct so it should match the average case
- */
-void
-InitVelocityData(DeviceVelocityPtr vel)
-{
- memset(vel, 0, sizeof(DeviceVelocityRec));
-
- vel->corr_mul = 10.0; /* dots per 10 milisecond should be usable */
- vel->const_acceleration = 1.0; /* no acceleration/deceleration */
- vel->reset_time = 300;
- vel->use_softening = 1;
- vel->min_acceleration = 1.0; /* don't decelerate */
- vel->max_rel_diff = 0.2;
- vel->max_diff = 1.0;
- vel->initial_range = 2;
- vel->average_accel = TRUE;
- SetAccelerationProfile(vel, AccelProfileClassic);
- InitTrackers(vel, 16);
-}
-
-
-/**
- * Clean up
- */
-void
-FreeVelocityData(DeviceVelocityPtr vel){
- free(vel->tracker);
- SetAccelerationProfile(vel, PROFILE_UNINITIALIZE);
-}
-
-
-/*
- * dix uninit helper, called through scheme
- */
-void
-AccelerationDefaultCleanup(DeviceIntPtr dev)
-{
- /*sanity check*/
- if( dev->valuator->accelScheme.AccelSchemeProc == acceleratePointerPredictable
- && dev->valuator->accelScheme.accelData != NULL){
- dev->valuator->accelScheme.AccelSchemeProc = NULL;
- FreeVelocityData(dev->valuator->accelScheme.accelData);
- free(dev->valuator->accelScheme.accelData);
- dev->valuator->accelScheme.accelData = NULL;
- DeletePredictableAccelerationProperties(dev);
- }
-}
-
-
-/*************************
- * Input property support
- ************************/
-
-/**
- * choose profile
- */
-static int
-AccelSetProfileProperty(DeviceIntPtr dev, Atom atom,
- XIPropertyValuePtr val, BOOL checkOnly)
-{
- DeviceVelocityPtr vel;
- int profile, *ptr = &profile;
- int rc;
- int nelem = 1;
-
- if (atom != XIGetKnownProperty(ACCEL_PROP_PROFILE_NUMBER))
- return Success;
-
- vel = GetDevicePredictableAccelData(dev);
- if (!vel)
- return BadValue;
- rc = XIPropToInt(val, &nelem, &ptr);
-
- if(checkOnly)
- {
- if (rc)
- return rc;
-
- if (GetAccelerationProfile(vel, profile) == NULL)
- return BadValue;
- } else
- SetAccelerationProfile(vel, profile);
-
- return Success;
-}
-
-static long
-AccelInitProfileProperty(DeviceIntPtr dev, DeviceVelocityPtr vel)
-{
- int profile = vel->statistics.profile_number;
- Atom prop_profile_number = XIGetKnownProperty(ACCEL_PROP_PROFILE_NUMBER);
-
- XIChangeDeviceProperty(dev, prop_profile_number, XA_INTEGER, 32,
- PropModeReplace, 1, &profile, FALSE);
- XISetDevicePropertyDeletable(dev, prop_profile_number, FALSE);
- return XIRegisterPropertyHandler(dev, AccelSetProfileProperty, NULL, NULL);
-}
-
-/**
- * constant deceleration
- */
-static int
-AccelSetDecelProperty(DeviceIntPtr dev, Atom atom,
- XIPropertyValuePtr val, BOOL checkOnly)
-{
- DeviceVelocityPtr vel;
- float v, *ptr = &v;
- int rc;
- int nelem = 1;
-
- if (atom != XIGetKnownProperty(ACCEL_PROP_CONSTANT_DECELERATION))
- return Success;
-
- vel = GetDevicePredictableAccelData(dev);
- if (!vel)
- return BadValue;
- rc = XIPropToFloat(val, &nelem, &ptr);
-
- if(checkOnly)
- {
- if (rc)
- return rc;
- return (v >= 1.0f) ? Success : BadValue;
- }
-
- if(v >= 1.0f)
- vel->const_acceleration = 1/v;
-
- return Success;
-}
-
-static long
-AccelInitDecelProperty(DeviceIntPtr dev, DeviceVelocityPtr vel)
-{
- float fval = 1.0/vel->const_acceleration;
- Atom prop_const_decel = XIGetKnownProperty(ACCEL_PROP_CONSTANT_DECELERATION);
- XIChangeDeviceProperty(dev, prop_const_decel,
- XIGetKnownProperty(XATOM_FLOAT), 32,
- PropModeReplace, 1, &fval, FALSE);
- XISetDevicePropertyDeletable(dev, prop_const_decel, FALSE);
- return XIRegisterPropertyHandler(dev, AccelSetDecelProperty, NULL, NULL);
-}
-
-
-/**
- * adaptive deceleration
- */
-static int
-AccelSetAdaptDecelProperty(DeviceIntPtr dev, Atom atom,
- XIPropertyValuePtr val, BOOL checkOnly)
-{
- DeviceVelocityPtr veloc;
- float v, *ptr = &v;
- int rc;
- int nelem = 1;
-
- if (atom != XIGetKnownProperty(ACCEL_PROP_ADAPTIVE_DECELERATION))
- return Success;
-
- veloc = GetDevicePredictableAccelData(dev);
- if (!veloc)
- return BadValue;
- rc = XIPropToFloat(val, &nelem, &ptr);
-
- if(checkOnly)
- {
- if (rc)
- return rc;
- return (v >= 1.0f) ? Success : BadValue;
- }
-
- if(v >= 1.0f)
- veloc->min_acceleration = 1/v;
-
- return Success;
-}
-
-static long
-AccelInitAdaptDecelProperty(DeviceIntPtr dev, DeviceVelocityPtr vel)
-{
- float fval = 1.0/vel->min_acceleration;
- Atom prop_adapt_decel = XIGetKnownProperty(ACCEL_PROP_ADAPTIVE_DECELERATION);
-
- XIChangeDeviceProperty(dev, prop_adapt_decel, XIGetKnownProperty(XATOM_FLOAT), 32,
- PropModeReplace, 1, &fval, FALSE);
- XISetDevicePropertyDeletable(dev, prop_adapt_decel, FALSE);
- return XIRegisterPropertyHandler(dev, AccelSetAdaptDecelProperty, NULL, NULL);
-}
-
-
-/**
- * velocity scaling
- */
-static int
-AccelSetScaleProperty(DeviceIntPtr dev, Atom atom,
- XIPropertyValuePtr val, BOOL checkOnly)
-{
- DeviceVelocityPtr vel;
- float v, *ptr = &v;
- int rc;
- int nelem = 1;
-
- if (atom != XIGetKnownProperty(ACCEL_PROP_VELOCITY_SCALING))
- return Success;
-
- vel = GetDevicePredictableAccelData(dev);
- if (!vel)
- return BadValue;
- rc = XIPropToFloat(val, &nelem, &ptr);
-
- if (checkOnly)
- {
- if (rc)
- return rc;
-
- return (v > 0) ? Success : BadValue;
- }
-
- if(v > 0)
- vel->corr_mul = v;
-
- return Success;
-}
-
-static long
-AccelInitScaleProperty(DeviceIntPtr dev, DeviceVelocityPtr vel)
-{
- float fval = vel->corr_mul;
- Atom prop_velo_scale = XIGetKnownProperty(ACCEL_PROP_VELOCITY_SCALING);
-
- XIChangeDeviceProperty(dev, prop_velo_scale, XIGetKnownProperty(XATOM_FLOAT), 32,
- PropModeReplace, 1, &fval, FALSE);
- XISetDevicePropertyDeletable(dev, prop_velo_scale, FALSE);
- return XIRegisterPropertyHandler(dev, AccelSetScaleProperty, NULL, NULL);
-}
-
-BOOL
-InitializePredictableAccelerationProperties(DeviceIntPtr dev)
-{
- DeviceVelocityPtr vel = GetDevicePredictableAccelData(dev);
-
- if(!vel)
- return FALSE;
-
- vel->prop_handlers[0] = AccelInitProfileProperty(dev, vel);
- vel->prop_handlers[1] = AccelInitDecelProperty(dev, vel);
- vel->prop_handlers[2] = AccelInitAdaptDecelProperty(dev, vel);
- vel->prop_handlers[3] = AccelInitScaleProperty(dev, vel);
-
- return TRUE;
-}
-
-BOOL
-DeletePredictableAccelerationProperties(DeviceIntPtr dev)
-{
- DeviceVelocityPtr vel;
- Atom prop;
- int i;
-
- prop = XIGetKnownProperty(ACCEL_PROP_VELOCITY_SCALING);
- XIDeleteDeviceProperty(dev, prop, FALSE);
- prop = XIGetKnownProperty(ACCEL_PROP_ADAPTIVE_DECELERATION);
- XIDeleteDeviceProperty(dev, prop, FALSE);
- prop = XIGetKnownProperty(ACCEL_PROP_CONSTANT_DECELERATION);
- XIDeleteDeviceProperty(dev, prop, FALSE);
- prop = XIGetKnownProperty(ACCEL_PROP_PROFILE_NUMBER);
- XIDeleteDeviceProperty(dev, prop, FALSE);
-
- vel = GetDevicePredictableAccelData(dev);
- for (i = 0; vel && i < NPROPS_PREDICTABLE_ACCEL; i++)
- if (vel->prop_handlers[i])
- XIUnregisterPropertyHandler(dev, vel->prop_handlers[i]);
-
- return TRUE;
-}
-
-/*********************
- * Tracking logic
- ********************/
-
-void
-InitTrackers(DeviceVelocityPtr vel, int ntracker)
-{
- if(ntracker < 1){
- ErrorF("(dix ptracc) invalid number of trackers\n");
- return;
- }
- free(vel->tracker);
- vel->tracker = (MotionTrackerPtr)malloc(ntracker * sizeof(MotionTracker));
- memset(vel->tracker, 0, ntracker * sizeof(MotionTracker));
- vel->num_tracker = ntracker;
-}
-
-/**
- * return a bit field of possible directions.
- * 0 = N, 2 = E, 4 = S, 6 = W, in-between is as you guess.
- * There's no reason against widening to more precise directions (<45 degrees),
- * should it not perform well. All this is needed for is sort out non-linear
- * motion, so precision isn't paramount. However, one should not flag direction
- * too narrow, since it would then cut the linear segment to zero size way too
- * often.
- */
-static int
-DoGetDirection(int dx, int dy){
- float r;
- int i1, i2;
- /* on insignificant mickeys, flag 135 degrees */
- if(abs(dx) < 2 && abs(dy < 2)){
- /* first check diagonal cases */
- if(dx > 0 && dy > 0)
- return 4+8+16;
- if(dx > 0 && dy < 0)
- return 1+2+4;
- if(dx < 0 && dy < 0)
- return 1+128+64;
- if(dx < 0 && dy > 0)
- return 16+32+64;
- /* check axis-aligned directions */
- if(dx > 0)
- return 2+4+8; /*E*/
- if(dx < 0)
- return 128+64+32; /*W*/
- if(dy > 0)
- return 32+16+8; /*S*/
- if(dy < 0)
- return 128+1+2; /*N*/
- return 255; /* shouldn't happen */
- }
- /* else, compute angle and set appropriate flags */
-#ifdef _ISOC99_SOURCE
- r = atan2f(dy, dx);
-#else
- r = atan2(dy, dx);
-#endif
- /* find direction. We avoid r to become negative,
- * since C has no well-defined modulo for such cases. */
- r = (r+(M_PI*2.5))/(M_PI/4);
- /* this intends to flag 2 directions (90 degrees),
- * except on very well-aligned mickeys. */
- i1 = (int)(r+0.1) % 8;
- i2 = (int)(r+0.9) % 8;
- if(i1 < 0 || i1 > 7 || i2 < 0 || i2 > 7)
- return 255; /* shouldn't happen */
- return 1 << i1 | 1 << i2;
-}
-
-#define DIRECTION_CACHE_RANGE 5
-#define DIRECTION_CACHE_SIZE (DIRECTION_CACHE_RANGE*2+1)
-
-/* cache DoGetDirection(). */
-static int
-GetDirection(int dx, int dy){
- static int cache[DIRECTION_CACHE_SIZE][DIRECTION_CACHE_SIZE];
- int i;
- if (abs(dx) <= DIRECTION_CACHE_RANGE &&
- abs(dy) <= DIRECTION_CACHE_RANGE) {
- /* cacheable */
- i = cache[DIRECTION_CACHE_RANGE+dx][DIRECTION_CACHE_RANGE+dy];
- if(i != 0){
- return i;
- }else{
- i = DoGetDirection(dx, dy);
- cache[DIRECTION_CACHE_RANGE+dx][DIRECTION_CACHE_RANGE+dy] = i;
- return i;
- }
- }else{
- /* non-cacheable */
- return DoGetDirection(dx, dy);
- }
-}
-
-#undef DIRECTION_CACHE_RANGE
-#undef DIRECTION_CACHE_SIZE
-
-
-/* convert offset (age) to array index */
-#define TRACKER_INDEX(s, d) (((s)->num_tracker + (s)->cur_tracker - (d)) % (s)->num_tracker)
-
-static inline void
-FeedTrackers(DeviceVelocityPtr vel, int dx, int dy, int cur_t)
-{
- int n;
- for(n = 0; n < vel->num_tracker; n++){
- vel->tracker[n].dx += dx;
- vel->tracker[n].dy += dy;
- }
- n = (vel->cur_tracker + 1) % vel->num_tracker;
- vel->tracker[n].dx = 0;
- vel->tracker[n].dy = 0;
- vel->tracker[n].time = cur_t;
- vel->tracker[n].dir = GetDirection(dx, dy);
- DebugAccelF("(dix prtacc) motion [dx: %i dy: %i dir:%i diff: %i]\n",
- dx, dy, vel->tracker[n].dir,
- cur_t - vel->tracker[vel->cur_tracker].time);
- vel->cur_tracker = n;
-}
-
-/**
- * calc velocity for given tracker, with
- * velocity scaling.
- * This assumes linear motion.
- */
-static float
-CalcTracker(DeviceVelocityPtr vel, int offset, int cur_t){
- int index = TRACKER_INDEX(vel, offset);
- float dist = sqrt( vel->tracker[index].dx * vel->tracker[index].dx
- + vel->tracker[index].dy * vel->tracker[index].dy);
- int dtime = cur_t - vel->tracker[index].time;
- if(dtime > 0)
- return dist / dtime;
- else
- return 0;/* synonymous for NaN, since we're not C99 */
-}
-
-/* find the most plausible velocity. That is, the most distant
- * (in time) tracker which isn't too old, beyond a linear partition,
- * or simply too much off initial velocity.
- *
- * May return 0.
- */
-static float
-QueryTrackers(DeviceVelocityPtr vel, int cur_t){
- int n, offset, dir = 255, i = -1, age_ms;
- /* initial velocity: a low-offset, valid velocity */
- float iveloc = 0, res = 0, tmp, vdiff;
- float vfac = vel->corr_mul * vel->const_acceleration; /* premultiply */
- /* loop from current to older data */
- for(offset = 1; offset < vel->num_tracker; offset++){
- n = TRACKER_INDEX(vel, offset);
-
- age_ms = cur_t - vel->tracker[n].time;
-
- /* bail out if data is too old and protect from overrun */
- if (age_ms >= vel->reset_time || age_ms < 0) {
- DebugAccelF("(dix prtacc) query: tracker too old\n");
- break;
- }
-
- /*
- * this heuristic avoids using the linear-motion velocity formula
- * in CalcTracker() on motion that isn't exactly linear. So to get
- * even more precision we could subdivide as a final step, so possible
- * non-linearities are accounted for.
- */
- dir &= vel->tracker[n].dir;
- if(dir == 0){
- DebugAccelF("(dix prtacc) query: no longer linear\n");
- /* instead of breaking it we might also inspect the partition after,
- * but actual improvement with this is probably rare. */
- break;
- }
-
- tmp = CalcTracker(vel, offset, cur_t) * vfac;
-
- if ((iveloc == 0 || offset <= vel->initial_range) && tmp != 0) {
- /* set initial velocity and result */
- res = iveloc = tmp;
- i = offset;
- } else if (iveloc != 0 && tmp != 0) {
- vdiff = fabs(iveloc - tmp);
- if (vdiff <= vel->max_diff ||
- vdiff/(iveloc + tmp) < vel->max_rel_diff) {
- /* we're in range with the initial velocity,
- * so this result is likely better
- * (it contains more information). */
- res = tmp;
- i = offset;
- }else{
- /* we're not in range, quit - it won't get better. */
- DebugAccelF("(dix prtacc) query: tracker too different:"
- " old %2.2f initial %2.2f diff: %2.2f\n",
- tmp, iveloc, vdiff);
- break;
- }
- }
- }
- if(offset == vel->num_tracker){
- DebugAccelF("(dix prtacc) query: last tracker in effect\n");
- i = vel->num_tracker-1;
- }
- if(i>=0){
- n = TRACKER_INDEX(vel, i);
- DebugAccelF("(dix prtacc) result: offset %i [dx: %i dy: %i diff: %i]\n",
- i,
- vel->tracker[n].dx,
- vel->tracker[n].dy,
- cur_t - vel->tracker[n].time);
- }
- return res;
-}
-
-#undef TRACKER_INDEX
-
-/**
- * Perform velocity approximation based on 2D 'mickeys' (mouse motion delta).
- * return true if non-visible state reset is suggested
- */
-short
-ProcessVelocityData2D(
- DeviceVelocityPtr vel,
- int dx,
- int dy,
- int time)
-{
- float velocity;
-
- vel->last_velocity = vel->velocity;
-
- FeedTrackers(vel, dx, dy, time);
-
- velocity = QueryTrackers(vel, time);
-
- vel->velocity = velocity;
- return velocity == 0;
-}
-
-/**
- * this flattens significant ( > 1) mickeys a little bit for more steady
- * constant-velocity response
- */
-static inline float
-ApplySimpleSoftening(int od, int d)
-{
- float res = d;
- if (d <= 1 && d >= -1)
- return res;
- if (d > od)
- res -= 0.5;
- else if (d < od)
- res += 0.5;
- return res;
-}
-
-
-static void
-ApplySofteningAndConstantDeceleration(
- DeviceVelocityPtr vel,
- int dx,
- int dy,
- float* fdx,
- float* fdy,
- short do_soften)
-{
- if (do_soften && vel->use_softening) {
- *fdx = ApplySimpleSoftening(vel->last_dx, dx);
- *fdy = ApplySimpleSoftening(vel->last_dy, dy);
- } else {
- *fdx = dx;
- *fdy = dy;
- }
-
- *fdx *= vel->const_acceleration;
- *fdy *= vel->const_acceleration;
-}
-
-/*
- * compute the acceleration for given velocity and enforce min_acceleartion
- */
-float
-BasicComputeAcceleration(
- DeviceIntPtr dev,
- DeviceVelocityPtr vel,
- float velocity,
- float threshold,
- float acc){
-
- float result;
- result = vel->Profile(dev, vel, velocity, threshold, acc);
-
- /* enforce min_acceleration */
- if (result < vel->min_acceleration)
- result = vel->min_acceleration;
- return result;
-}
-
-/**
- * Compute acceleration. Takes into account averaging, nv-reset, etc.
- */
-static float
-ComputeAcceleration(
- DeviceIntPtr dev,
- DeviceVelocityPtr vel,
- float threshold,
- float acc){
- float res;
-
- if(vel->velocity <= 0){
- DebugAccelF("(dix ptracc) profile skipped\n");
- /*
- * If we have no idea about device velocity, don't pretend it.
- */
- return 1;
- }
-
- if(vel->average_accel && vel->velocity != vel->last_velocity){
- /* use simpson's rule to average acceleration between
- * current and previous velocity.
- * Though being the more natural choice, it causes a minor delay
- * in comparison, so it can be disabled. */
- res = BasicComputeAcceleration(
- dev, vel, vel->velocity, threshold, acc);
- res += BasicComputeAcceleration(
- dev, vel, vel->last_velocity, threshold, acc);
- res += 4.0f * BasicComputeAcceleration(dev, vel,
- (vel->last_velocity + vel->velocity) / 2,
- threshold, acc);
- res /= 6.0f;
- DebugAccelF("(dix ptracc) profile average [%.2f ... %.2f] is %.3f\n",
- vel->velocity, vel->last_velocity, res);
- return res;
- }else{
- res = BasicComputeAcceleration(dev, vel,
- vel->velocity, threshold, acc);
- DebugAccelF("(dix ptracc) profile sample [%.2f] is %.3f\n",
- vel->velocity, res);
- return res;
- }
-}
-
-
-/*****************************************
- * Acceleration functions and profiles
- ****************************************/
-
-/**
- * Polynomial function similar previous one, but with f(1) = 1
- */
-static float
-PolynomialAccelerationProfile(
- DeviceIntPtr dev,
- DeviceVelocityPtr vel,
- float velocity,
- float ignored,
- float acc)
-{
- return pow(velocity, (acc - 1.0) * 0.5);
-}
-
-
-/**
- * returns acceleration for velocity.
- * This profile selects the two functions like the old scheme did
- */
-static float
-ClassicProfile(
- DeviceIntPtr dev,
- DeviceVelocityPtr vel,
- float velocity,
- float threshold,
- float acc)
-{
- if (threshold > 0) {
- return SimpleSmoothProfile (dev,
- vel,
- velocity,
- threshold,
- acc);
- } else {
- return PolynomialAccelerationProfile (dev,
- vel,
- velocity,
- 0,
- acc);
- }
-}
-
-
-/**
- * Power profile
- * This has a completely smooth transition curve, i.e. no jumps in the
- * derivatives.
- *
- * This has the expense of overall response dependency on min-acceleration.
- * In effect, min_acceleration mimics const_acceleration in this profile.
- */
-static float
-PowerProfile(
- DeviceIntPtr dev,
- DeviceVelocityPtr vel,
- float velocity,
- float threshold,
- float acc)
-{
- float vel_dist;
-
- acc = (acc-1.0) * 0.1f + 1.0; /* without this, acc of 2 is unuseable */
-
- if (velocity <= threshold)
- return vel->min_acceleration;
- vel_dist = velocity - threshold;
- return (pow(acc, vel_dist)) * vel->min_acceleration;
-}
-
-
-/**
- * just a smooth function in [0..1] -> [0..1]
- * - point symmetry at 0.5
- * - f'(0) = f'(1) = 0
- * - starts faster than a sinoid
- * - smoothness C1 (Cinf if you dare to ignore endpoints)
- */
-static inline float
-CalcPenumbralGradient(float x){
- x *= 2.0f;
- x -= 1.0f;
- return 0.5f + (x * sqrt(1.0f - x*x) + asin(x))/M_PI;
-}
-
-
-/**
- * acceleration function similar to classic accelerated/unaccelerated,
- * but with smooth transition in between (and towards zero for adaptive dec.).
- */
-static float
-SimpleSmoothProfile(
- DeviceIntPtr dev,
- DeviceVelocityPtr vel,
- float velocity,
- float threshold,
- float acc)
-{
- if(velocity < 1.0f)
- return CalcPenumbralGradient(0.5 + velocity*0.5) * 2.0f - 1.0f;
- if(threshold < 1.0f)
- threshold = 1.0f;
- if (velocity <= threshold)
- return 1;
- velocity /= threshold;
- if (velocity >= acc)
- return acc;
- else
- return 1.0f + (CalcPenumbralGradient(velocity/acc) * (acc - 1.0f));
-}
-
-
-/**
- * This profile uses the first half of the penumbral gradient as a start
- * and then scales linearly.
- */
-static float
-SmoothLinearProfile(
- DeviceIntPtr dev,
- DeviceVelocityPtr vel,
- float velocity,
- float threshold,
- float acc)
-{
- float res, nv;
-
- if(acc > 1.0f)
- acc -= 1.0f; /*this is so acc = 1 is no acceleration */
- else
- return 1.0f;
-
- nv = (velocity - threshold) * acc * 0.5f;
-
- if(nv < 0){
- res = 0;
- }else if(nv < 2){
- res = CalcPenumbralGradient(nv*0.25f)*2.0f;
- }else{
- nv -= 2.0f;
- res = nv * 2.0f / M_PI /* steepness of gradient at 0.5 */
- + 1.0f; /* gradient crosses 2|1 */
- }
- res += vel->min_acceleration;
- return res;
-}
-
-
-/**
- * From 0 to threshold, the response graduates smoothly from min_accel to
- * acceleration. Beyond threshold it is exactly the specified acceleration.
- */
-static float
-SmoothLimitedProfile(
- DeviceIntPtr dev,
- DeviceVelocityPtr vel,
- float velocity,
- float threshold,
- float acc)
-{
- float res;
-
- if(velocity >= threshold || threshold == 0.0f)
- return acc;
-
- velocity /= threshold; /* should be [0..1[ now */
-
- res = CalcPenumbralGradient(velocity) * (acc - vel->min_acceleration);
-
- return vel->min_acceleration + res;
-}
-
-
-static float
-LinearProfile(
- DeviceIntPtr dev,
- DeviceVelocityPtr vel,
- float velocity,
- float threshold,
- float acc)
-{
- return acc * velocity;
-}
-
-static float
-NoProfile(
- DeviceIntPtr dev,
- DeviceVelocityPtr vel,
- float velocity,
- float threshold,
- float acc)
-{
- return 1.0f;
-}
-
-static PointerAccelerationProfileFunc
-GetAccelerationProfile(
- DeviceVelocityPtr vel,
- int profile_num)
-{
- switch(profile_num){
- case AccelProfileClassic:
- return ClassicProfile;
- case AccelProfileDeviceSpecific:
- return vel->deviceSpecificProfile;
- case AccelProfilePolynomial:
- return PolynomialAccelerationProfile;
- case AccelProfileSmoothLinear:
- return SmoothLinearProfile;
- case AccelProfileSimple:
- return SimpleSmoothProfile;
- case AccelProfilePower:
- return PowerProfile;
- case AccelProfileLinear:
- return LinearProfile;
- case AccelProfileSmoothLimited:
- return SmoothLimitedProfile;
- case AccelProfileNone:
- return NoProfile;
- default:
- return NULL;
- }
-}
-
-/**
- * Set the profile by number.
- * Intended to make profiles exchangeable at runtime.
- * If you created a profile, give it a number here and in the header to
- * make it selectable. In case some profile-specific init is needed, here
- * would be a good place, since FreeVelocityData() also calls this with
- * PROFILE_UNINITIALIZE.
- *
- * returns FALSE if profile number is unavailable, TRUE otherwise.
- */
-int
-SetAccelerationProfile(
- DeviceVelocityPtr vel,
- int profile_num)
-{
- PointerAccelerationProfileFunc profile;
- profile = GetAccelerationProfile(vel, profile_num);
-
- if(profile == NULL && profile_num != PROFILE_UNINITIALIZE)
- return FALSE;
-
- /* Here one could free old profile-private data */
- free(vel->profile_private);
- vel->profile_private = NULL;
- /* Here one could init profile-private data */
- vel->Profile = profile;
- vel->statistics.profile_number = profile_num;
- return TRUE;
-}
-
-/**********************************************
- * driver interaction
- **********************************************/
-
-
-/**
- * device-specific profile
- *
- * The device-specific profile is intended as a hook for a driver
- * which may want to provide an own acceleration profile.
- * It should not rely on profile-private data, instead
- * it should do init/uninit in the driver (ie. with DEVICE_INIT and friends).
- * Users may override or choose it.
- */
-void
-SetDeviceSpecificAccelerationProfile(
- DeviceVelocityPtr vel,
- PointerAccelerationProfileFunc profile)
-{
- if(vel)
- vel->deviceSpecificProfile = profile;
-}
-
-/**
- * Use this function to obtain a DeviceVelocityPtr for a device. Will return NULL if
- * the predictable acceleration scheme is not in effect.
- */
-DeviceVelocityPtr
-GetDevicePredictableAccelData(
- DeviceIntPtr dev)
-{
- /*sanity check*/
- if(!dev){
- ErrorF("[dix] accel: DeviceIntPtr was NULL");
- return NULL;
- }
- if( dev->valuator &&
- dev->valuator->accelScheme.AccelSchemeProc ==
- acceleratePointerPredictable &&
- dev->valuator->accelScheme.accelData != NULL){
-
- return (DeviceVelocityPtr)dev->valuator->accelScheme.accelData;
- }
- return NULL;
-}
-
-/********************************
- * acceleration schemes
- *******************************/
-
-/**
- * Modifies valuators in-place.
- * This version employs a velocity approximation algorithm to
- * enable fine-grained predictable acceleration profiles.
- */
-void
-acceleratePointerPredictable(
- DeviceIntPtr dev,
- int first_valuator,
- int num_valuators,
- int *valuators,
- int evtime)
-{
- float mult = 0.0;
- int dx = 0, dy = 0;
- int *px = NULL, *py = NULL;
- DeviceVelocityPtr velocitydata =
- (DeviceVelocityPtr) dev->valuator->accelScheme.accelData;
- float fdx, fdy, tmp; /* no need to init */
- Bool soften = TRUE;
-
- if (!num_valuators || !valuators || !velocitydata)
- return;
-
- if (velocitydata->statistics.profile_number == AccelProfileNone &&
- velocitydata->const_acceleration == 1.0f) {
- return; /*we're inactive anyway, so skip the whole thing.*/
- }
-
- if (first_valuator == 0) {
- dx = valuators[0];
- px = &valuators[0];
- }
- if (first_valuator <= 1 && num_valuators >= (2 - first_valuator)) {
- dy = valuators[1 - first_valuator];
- py = &valuators[1 - first_valuator];
- }
-
- if (dx || dy){
- /* reset non-visible state? */
- if (ProcessVelocityData2D(velocitydata, dx , dy, evtime)) {
- soften = FALSE;
- }
-
- if (dev->ptrfeed && dev->ptrfeed->ctrl.num) {
- /* invoke acceleration profile to determine acceleration */
- mult = ComputeAcceleration (dev, velocitydata,
- dev->ptrfeed->ctrl.threshold,
- (float)dev->ptrfeed->ctrl.num /
- (float)dev->ptrfeed->ctrl.den);
-
- if(mult != 1.0 || velocitydata->const_acceleration != 1.0) {
- ApplySofteningAndConstantDeceleration( velocitydata,
- dx, dy,
- &fdx, &fdy,
- (mult > 1.0) && soften);
-
- if (dx) {
- tmp = mult * fdx + dev->last.remainder[0];
- /* Since it may not be apparent: lrintf() does not offer
- * strong statements about rounding; however because we
- * process each axis conditionally, there's no danger
- * of a toggling remainder. Its lack of guarantees likely
- * makes it faster on the average target. */
- *px = lrintf(tmp);
- dev->last.remainder[0] = tmp - (float)*px;
- }
- if (dy) {
- tmp = mult * fdy + dev->last.remainder[1];
- *py = lrintf(tmp);
- dev->last.remainder[1] = tmp - (float)*py;
- }
- DebugAccelF("pos (%i | %i) remainders x: %.3f y: %.3f delta x:%.3f y:%.3f\n",
- *px, *py, dev->last.remainder[0], dev->last.remainder[1], fdx, fdy);
- }
- }
- }
- /* remember last motion delta (for softening/slow movement treatment) */
- velocitydata->last_dx = dx;
- velocitydata->last_dy = dy;
-}
-
-
-
-/**
- * Originally a part of xf86PostMotionEvent; modifies valuators
- * in-place. Retained mostly for embedded scenarios.
- */
-void
-acceleratePointerLightweight(
- DeviceIntPtr dev,
- int first_valuator,
- int num_valuators,
- int *valuators,
- int ignored)
-{
- float mult = 0.0;
- int dx = 0, dy = 0;
- int *px = NULL, *py = NULL;
-
- if (!num_valuators || !valuators)
- return;
-
- if (first_valuator == 0) {
- dx = valuators[0];
- px = &valuators[0];
- }
- if (first_valuator <= 1 && num_valuators >= (2 - first_valuator)) {
- dy = valuators[1 - first_valuator];
- py = &valuators[1 - first_valuator];
- }
-
- if (!dx && !dy)
- return;
-
- if (dev->ptrfeed && dev->ptrfeed->ctrl.num) {
- /* modeled from xf86Events.c */
- if (dev->ptrfeed->ctrl.threshold) {
- if ((abs(dx) + abs(dy)) >= dev->ptrfeed->ctrl.threshold) {
- dev->last.remainder[0] = ((float)dx *
- (float)(dev->ptrfeed->ctrl.num)) /
- (float)(dev->ptrfeed->ctrl.den) +
- dev->last.remainder[0];
- if (px) {
- *px = (int)dev->last.remainder[0];
- dev->last.remainder[0] = dev->last.remainder[0] -
- (float)(*px);
- }
-
- dev->last.remainder[1] = ((float)dy *
- (float)(dev->ptrfeed->ctrl.num)) /
- (float)(dev->ptrfeed->ctrl.den) +
- dev->last.remainder[1];
- if (py) {
- *py = (int)dev->last.remainder[1];
- dev->last.remainder[1] = dev->last.remainder[1] -
- (float)(*py);
- }
- }
- }
- else {
- mult = pow((float)dx * (float)dx + (float)dy * (float)dy,
- ((float)(dev->ptrfeed->ctrl.num) /
- (float)(dev->ptrfeed->ctrl.den) - 1.0) /
- 2.0) / 2.0;
- if (dx) {
- dev->last.remainder[0] = mult * (float)dx +
- dev->last.remainder[0];
- *px = (int)dev->last.remainder[0];
- dev->last.remainder[0] = dev->last.remainder[0] -
- (float)(*px);
- }
- if (dy) {
- dev->last.remainder[1] = mult * (float)dy +
- dev->last.remainder[1];
- *py = (int)dev->last.remainder[1];
- dev->last.remainder[1] = dev->last.remainder[1] -
- (float)(*py);
- }
- }
- }
-}
+/*
+ *
+ * Copyright © 2006-2009 Simon Thum simon dot thum at gmx dot de
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#ifdef HAVE_DIX_CONFIG_H
+#include <dix-config.h>
+#endif
+
+#include <math.h>
+#include <ptrveloc.h>
+#include <exevents.h>
+#include <X11/Xatom.h>
+
+#include <xserver-properties.h>
+
+/*****************************************************************************
+ * Predictable pointer acceleration
+ *
+ * 2006-2009 by Simon Thum (simon [dot] thum [at] gmx de)
+ *
+ * Serves 3 complementary functions:
+ * 1) provide a sophisticated ballistic velocity estimate to improve
+ * the relation between velocity (of the device) and acceleration
+ * 2) make arbitrary acceleration profiles possible
+ * 3) decelerate by two means (constant and adaptive) if enabled
+ *
+ * Important concepts are the
+ *
+ * - Scheme
+ * which selects the basic algorithm
+ * (see devices.c/InitPointerAccelerationScheme)
+ * - Profile
+ * which returns an acceleration
+ * for a given velocity
+ *
+ * The profile can be selected by the user at runtime.
+ * The classic profile is intended to cleanly perform old-style
+ * function selection (threshold =/!= 0)
+ *
+ ****************************************************************************/
+
+/* fwds */
+int
+SetAccelerationProfile(DeviceVelocityPtr vel, int profile_num);
+static float
+SimpleSmoothProfile(DeviceIntPtr dev, DeviceVelocityPtr vel, float velocity,
+ float threshold, float acc);
+static PointerAccelerationProfileFunc
+GetAccelerationProfile(DeviceVelocityPtr vel, int profile_num);
+static BOOL
+InitializePredictableAccelerationProperties(DeviceIntPtr dev);
+static BOOL
+DeletePredictableAccelerationProperties(DeviceIntPtr dev);
+
+/*#define PTRACCEL_DEBUGGING*/
+
+#ifdef PTRACCEL_DEBUGGING
+#define DebugAccelF ErrorF
+#else
+#define DebugAccelF(...) /* */
+#endif
+
+/********************************
+ * Init/Uninit
+ *******************************/
+
+/* some int which is not a profile number */
+#define PROFILE_UNINITIALIZE (-100)
+
+
+/**
+ * Init DeviceVelocity struct so it should match the average case
+ */
+void
+InitVelocityData(DeviceVelocityPtr vel)
+{
+ memset(vel, 0, sizeof(DeviceVelocityRec));
+
+ vel->corr_mul = 10.0; /* dots per 10 milisecond should be usable */
+ vel->const_acceleration = 1.0; /* no acceleration/deceleration */
+ vel->reset_time = 300;
+ vel->use_softening = 1;
+ vel->min_acceleration = 1.0; /* don't decelerate */
+ vel->max_rel_diff = 0.2;
+ vel->max_diff = 1.0;
+ vel->initial_range = 2;
+ vel->average_accel = TRUE;
+ SetAccelerationProfile(vel, AccelProfileClassic);
+ InitTrackers(vel, 16);
+}
+
+
+/**
+ * Clean up DeviceVelocityRec
+ */
+void
+FreeVelocityData(DeviceVelocityPtr vel){
+ free(vel->tracker);
+ SetAccelerationProfile(vel, PROFILE_UNINITIALIZE);
+}
+
+
+/**
+ * Init predictable scheme
+ */
+Bool
+InitPredictableAccelerationScheme(DeviceIntPtr dev,
+ ValuatorAccelerationPtr protoScheme) {
+ DeviceVelocityPtr vel;
+ ValuatorAccelerationRec scheme;
+ scheme = *protoScheme;
+ vel = calloc(1, sizeof(DeviceVelocityRec));
+ if (!vel)
+ return FALSE;
+ InitVelocityData(vel);
+ scheme.accelData = vel;
+ dev->valuator->accelScheme = scheme;
+ InitializePredictableAccelerationProperties(dev);
+ return TRUE;
+}
+
+
+/**
+ * Uninit scheme
+ */
+void
+AccelerationDefaultCleanup(DeviceIntPtr dev)
+{
+ /*sanity check*/
+ if( dev->valuator->accelScheme.AccelSchemeProc == acceleratePointerPredictable
+ && dev->valuator->accelScheme.accelData != NULL){
+ dev->valuator->accelScheme.AccelSchemeProc = NULL;
+ FreeVelocityData(dev->valuator->accelScheme.accelData);
+ free(dev->valuator->accelScheme.accelData);
+ dev->valuator->accelScheme.accelData = NULL;
+ DeletePredictableAccelerationProperties(dev);
+ }
+}
+
+
+/*************************
+ * Input property support
+ ************************/
+
+/**
+ * choose profile
+ */
+static int
+AccelSetProfileProperty(DeviceIntPtr dev, Atom atom,
+ XIPropertyValuePtr val, BOOL checkOnly)
+{
+ DeviceVelocityPtr vel;
+ int profile, *ptr = &profile;
+ int rc;
+ int nelem = 1;
+
+ if (atom != XIGetKnownProperty(ACCEL_PROP_PROFILE_NUMBER))
+ return Success;
+
+ vel = GetDevicePredictableAccelData(dev);
+ if (!vel)
+ return BadValue;
+ rc = XIPropToInt(val, &nelem, &ptr);
+
+ if(checkOnly)
+ {
+ if (rc)
+ return rc;
+
+ if (GetAccelerationProfile(vel, profile) == NULL)
+ return BadValue;
+ } else
+ SetAccelerationProfile(vel, profile);
+
+ return Success;
+}
+
+static long
+AccelInitProfileProperty(DeviceIntPtr dev, DeviceVelocityPtr vel)
+{
+ int profile = vel->statistics.profile_number;
+ Atom prop_profile_number = XIGetKnownProperty(ACCEL_PROP_PROFILE_NUMBER);
+
+ XIChangeDeviceProperty(dev, prop_profile_number, XA_INTEGER, 32,
+ PropModeReplace, 1, &profile, FALSE);
+ XISetDevicePropertyDeletable(dev, prop_profile_number, FALSE);
+ return XIRegisterPropertyHandler(dev, AccelSetProfileProperty, NULL, NULL);
+}
+
+/**
+ * constant deceleration
+ */
+static int
+AccelSetDecelProperty(DeviceIntPtr dev, Atom atom,
+ XIPropertyValuePtr val, BOOL checkOnly)
+{
+ DeviceVelocityPtr vel;
+ float v, *ptr = &v;
+ int rc;
+ int nelem = 1;
+
+ if (atom != XIGetKnownProperty(ACCEL_PROP_CONSTANT_DECELERATION))
+ return Success;
+
+ vel = GetDevicePredictableAccelData(dev);
+ if (!vel)
+ return BadValue;
+ rc = XIPropToFloat(val, &nelem, &ptr);
+
+ if(checkOnly)
+ {
+ if (rc)
+ return rc;
+ return (v >= 1.0f) ? Success : BadValue;
+ }
+
+ if(v >= 1.0f)
+ vel->const_acceleration = 1/v;
+
+ return Success;
+}
+
+static long
+AccelInitDecelProperty(DeviceIntPtr dev, DeviceVelocityPtr vel)
+{
+ float fval = 1.0/vel->const_acceleration;
+ Atom prop_const_decel = XIGetKnownProperty(ACCEL_PROP_CONSTANT_DECELERATION);
+ XIChangeDeviceProperty(dev, prop_const_decel,
+ XIGetKnownProperty(XATOM_FLOAT), 32,
+ PropModeReplace, 1, &fval, FALSE);
+ XISetDevicePropertyDeletable(dev, prop_const_decel, FALSE);
+ return XIRegisterPropertyHandler(dev, AccelSetDecelProperty, NULL, NULL);
+}
+
+
+/**
+ * adaptive deceleration
+ */
+static int
+AccelSetAdaptDecelProperty(DeviceIntPtr dev, Atom atom,
+ XIPropertyValuePtr val, BOOL checkOnly)
+{
+ DeviceVelocityPtr veloc;
+ float v, *ptr = &v;
+ int rc;
+ int nelem = 1;
+
+ if (atom != XIGetKnownProperty(ACCEL_PROP_ADAPTIVE_DECELERATION))
+ return Success;
+
+ veloc = GetDevicePredictableAccelData(dev);
+ if (!veloc)
+ return BadValue;
+ rc = XIPropToFloat(val, &nelem, &ptr);
+
+ if(checkOnly)
+ {
+ if (rc)
+ return rc;
+ return (v >= 1.0f) ? Success : BadValue;
+ }
+
+ if(v >= 1.0f)
+ veloc->min_acceleration = 1/v;
+
+ return Success;
+}
+
+static long
+AccelInitAdaptDecelProperty(DeviceIntPtr dev, DeviceVelocityPtr vel)
+{
+ float fval = 1.0/vel->min_acceleration;
+ Atom prop_adapt_decel = XIGetKnownProperty(ACCEL_PROP_ADAPTIVE_DECELERATION);
+
+ XIChangeDeviceProperty(dev, prop_adapt_decel, XIGetKnownProperty(XATOM_FLOAT), 32,
+ PropModeReplace, 1, &fval, FALSE);
+ XISetDevicePropertyDeletable(dev, prop_adapt_decel, FALSE);
+ return XIRegisterPropertyHandler(dev, AccelSetAdaptDecelProperty, NULL, NULL);
+}
+
+
+/**
+ * velocity scaling
+ */
+static int
+AccelSetScaleProperty(DeviceIntPtr dev, Atom atom,
+ XIPropertyValuePtr val, BOOL checkOnly)
+{
+ DeviceVelocityPtr vel;
+ float v, *ptr = &v;
+ int rc;
+ int nelem = 1;
+
+ if (atom != XIGetKnownProperty(ACCEL_PROP_VELOCITY_SCALING))
+ return Success;
+
+ vel = GetDevicePredictableAccelData(dev);
+ if (!vel)
+ return BadValue;
+ rc = XIPropToFloat(val, &nelem, &ptr);
+
+ if (checkOnly)
+ {
+ if (rc)
+ return rc;
+
+ return (v > 0) ? Success : BadValue;
+ }
+
+ if(v > 0)
+ vel->corr_mul = v;
+
+ return Success;
+}
+
+static long
+AccelInitScaleProperty(DeviceIntPtr dev, DeviceVelocityPtr vel)
+{
+ float fval = vel->corr_mul;
+ Atom prop_velo_scale = XIGetKnownProperty(ACCEL_PROP_VELOCITY_SCALING);
+
+ XIChangeDeviceProperty(dev, prop_velo_scale, XIGetKnownProperty(XATOM_FLOAT), 32,
+ PropModeReplace, 1, &fval, FALSE);
+ XISetDevicePropertyDeletable(dev, prop_velo_scale, FALSE);
+ return XIRegisterPropertyHandler(dev, AccelSetScaleProperty, NULL, NULL);
+}
+
+BOOL
+InitializePredictableAccelerationProperties(DeviceIntPtr dev)
+{
+ DeviceVelocityPtr vel = GetDevicePredictableAccelData(dev);
+
+ if(!vel)
+ return FALSE;
+
+ vel->prop_handlers[0] = AccelInitProfileProperty(dev, vel);
+ vel->prop_handlers[1] = AccelInitDecelProperty(dev, vel);
+ vel->prop_handlers[2] = AccelInitAdaptDecelProperty(dev, vel);
+ vel->prop_handlers[3] = AccelInitScaleProperty(dev, vel);
+
+ return TRUE;
+}
+
+BOOL
+DeletePredictableAccelerationProperties(DeviceIntPtr dev)
+{
+ DeviceVelocityPtr vel;
+ Atom prop;
+ int i;
+
+ prop = XIGetKnownProperty(ACCEL_PROP_VELOCITY_SCALING);
+ XIDeleteDeviceProperty(dev, prop, FALSE);
+ prop = XIGetKnownProperty(ACCEL_PROP_ADAPTIVE_DECELERATION);
+ XIDeleteDeviceProperty(dev, prop, FALSE);
+ prop = XIGetKnownProperty(ACCEL_PROP_CONSTANT_DECELERATION);
+ XIDeleteDeviceProperty(dev, prop, FALSE);
+ prop = XIGetKnownProperty(ACCEL_PROP_PROFILE_NUMBER);
+ XIDeleteDeviceProperty(dev, prop, FALSE);
+
+ vel = GetDevicePredictableAccelData(dev);
+ for (i = 0; vel && i < NPROPS_PREDICTABLE_ACCEL; i++)
+ if (vel->prop_handlers[i])
+ XIUnregisterPropertyHandler(dev, vel->prop_handlers[i]);
+
+ return TRUE;
+}
+
+/*********************
+ * Tracking logic
+ ********************/
+
+void
+InitTrackers(DeviceVelocityPtr vel, int ntracker)
+{
+ if(ntracker < 1){
+ ErrorF("(dix ptracc) invalid number of trackers\n");
+ return;
+ }
+ free(vel->tracker);
+ vel->tracker = (MotionTrackerPtr)malloc(ntracker * sizeof(MotionTracker));
+ memset(vel->tracker, 0, ntracker * sizeof(MotionTracker));
+ vel->num_tracker = ntracker;
+}
+
+/**
+ * return a bit field of possible directions.
+ * 0 = N, 2 = E, 4 = S, 6 = W, in-between is as you guess.
+ * There's no reason against widening to more precise directions (<45 degrees),
+ * should it not perform well. All this is needed for is sort out non-linear
+ * motion, so precision isn't paramount. However, one should not flag direction
+ * too narrow, since it would then cut the linear segment to zero size way too
+ * often.
+ */
+static int
+DoGetDirection(int dx, int dy){
+ float r;
+ int i1, i2;
+ /* on insignificant mickeys, flag 135 degrees */
+ if(abs(dx) < 2 && abs(dy < 2)){
+ /* first check diagonal cases */
+ if(dx > 0 && dy > 0)
+ return 4+8+16;
+ if(dx > 0 && dy < 0)
+ return 1+2+4;
+ if(dx < 0 && dy < 0)
+ return 1+128+64;
+ if(dx < 0 && dy > 0)
+ return 16+32+64;
+ /* check axis-aligned directions */
+ if(dx > 0)
+ return 2+4+8; /*E*/
+ if(dx < 0)
+ return 128+64+32; /*W*/
+ if(dy > 0)
+ return 32+16+8; /*S*/
+ if(dy < 0)
+ return 128+1+2; /*N*/
+ return 255; /* shouldn't happen */
+ }
+ /* else, compute angle and set appropriate flags */
+#ifdef _ISOC99_SOURCE
+ r = atan2f(dy, dx);
+#else
+ r = atan2(dy, dx);
+#endif
+ /* find direction. We avoid r to become negative,
+ * since C has no well-defined modulo for such cases. */
+ r = (r+(M_PI*2.5))/(M_PI/4);
+ /* this intends to flag 2 directions (90 degrees),
+ * except on very well-aligned mickeys. */
+ i1 = (int)(r+0.1) % 8;
+ i2 = (int)(r+0.9) % 8;
+ if(i1 < 0 || i1 > 7 || i2 < 0 || i2 > 7)
+ return 255; /* shouldn't happen */
+ return 1 << i1 | 1 << i2;
+}
+
+#define DIRECTION_CACHE_RANGE 5
+#define DIRECTION_CACHE_SIZE (DIRECTION_CACHE_RANGE*2+1)
+
+/* cache DoGetDirection(). */
+static int
+GetDirection(int dx, int dy){
+ static int cache[DIRECTION_CACHE_SIZE][DIRECTION_CACHE_SIZE];
+ int i;
+ if (abs(dx) <= DIRECTION_CACHE_RANGE &&
+ abs(dy) <= DIRECTION_CACHE_RANGE) {
+ /* cacheable */
+ i = cache[DIRECTION_CACHE_RANGE+dx][DIRECTION_CACHE_RANGE+dy];
+ if(i != 0){
+ return i;
+ }else{
+ i = DoGetDirection(dx, dy);
+ cache[DIRECTION_CACHE_RANGE+dx][DIRECTION_CACHE_RANGE+dy] = i;
+ return i;
+ }
+ }else{
+ /* non-cacheable */
+ return DoGetDirection(dx, dy);
+ }
+}
+
+#undef DIRECTION_CACHE_RANGE
+#undef DIRECTION_CACHE_SIZE
+
+
+/* convert offset (age) to array index */
+#define TRACKER_INDEX(s, d) (((s)->num_tracker + (s)->cur_tracker - (d)) % (s)->num_tracker)
+
+static inline void
+FeedTrackers(DeviceVelocityPtr vel, int dx, int dy, int cur_t)
+{
+ int n;
+ for(n = 0; n < vel->num_tracker; n++){
+ vel->tracker[n].dx += dx;
+ vel->tracker[n].dy += dy;
+ }
+ n = (vel->cur_tracker + 1) % vel->num_tracker;
+ vel->tracker[n].dx = 0;
+ vel->tracker[n].dy = 0;
+ vel->tracker[n].time = cur_t;
+ vel->tracker[n].dir = GetDirection(dx, dy);
+ DebugAccelF("(dix prtacc) motion [dx: %i dy: %i dir:%i diff: %i]\n",
+ dx, dy, vel->tracker[n].dir,
+ cur_t - vel->tracker[vel->cur_tracker].time);
+ vel->cur_tracker = n;
+}
+
+/**
+ * calc velocity for given tracker, with
+ * velocity scaling.
+ * This assumes linear motion.
+ */
+static float
+CalcTracker(DeviceVelocityPtr vel, int offset, int cur_t){
+ int index = TRACKER_INDEX(vel, offset);
+ float dist = sqrt( vel->tracker[index].dx * vel->tracker[index].dx
+ + vel->tracker[index].dy * vel->tracker[index].dy);
+ int dtime = cur_t - vel->tracker[index].time;
+ if(dtime > 0)
+ return dist / dtime;
+ else
+ return 0;/* synonymous for NaN, since we're not C99 */
+}
+
+/* find the most plausible velocity. That is, the most distant
+ * (in time) tracker which isn't too old, beyond a linear partition,
+ * or simply too much off initial velocity.
+ *
+ * May return 0.
+ */
+static float
+QueryTrackers(DeviceVelocityPtr vel, int cur_t){
+ int n, offset, dir = 255, i = -1, age_ms;
+ /* initial velocity: a low-offset, valid velocity */
+ float iveloc = 0, res = 0, tmp, vdiff;
+ float vfac = vel->corr_mul * vel->const_acceleration; /* premultiply */
+ /* loop from current to older data */
+ for(offset = 1; offset < vel->num_tracker; offset++){
+ n = TRACKER_INDEX(vel, offset);
+
+ age_ms = cur_t - vel->tracker[n].time;
+
+ /* bail out if data is too old and protect from overrun */
+ if (age_ms >= vel->reset_time || age_ms < 0) {
+ DebugAccelF("(dix prtacc) query: tracker too old\n");
+ break;
+ }
+
+ /*
+ * this heuristic avoids using the linear-motion velocity formula
+ * in CalcTracker() on motion that isn't exactly linear. So to get
+ * even more precision we could subdivide as a final step, so possible
+ * non-linearities are accounted for.
+ */
+ dir &= vel->tracker[n].dir;
+ if(dir == 0){
+ DebugAccelF("(dix prtacc) query: no longer linear\n");
+ /* instead of breaking it we might also inspect the partition after,
+ * but actual improvement with this is probably rare. */
+ break;
+ }
+
+ tmp = CalcTracker(vel, offset, cur_t) * vfac;
+
+ if ((iveloc == 0 || offset <= vel->initial_range) && tmp != 0) {
+ /* set initial velocity and result */
+ res = iveloc = tmp;
+ i = offset;
+ } else if (iveloc != 0 && tmp != 0) {
+ vdiff = fabs(iveloc - tmp);
+ if (vdiff <= vel->max_diff ||
+ vdiff/(iveloc + tmp) < vel->max_rel_diff) {
+ /* we're in range with the initial velocity,
+ * so this result is likely better
+ * (it contains more information). */
+ res = tmp;
+ i = offset;
+ }else{
+ /* we're not in range, quit - it won't get better. */
+ DebugAccelF("(dix prtacc) query: tracker too different:"
+ " old %2.2f initial %2.2f diff: %2.2f\n",
+ tmp, iveloc, vdiff);
+ break;
+ }
+ }
+ }
+ if(offset == vel->num_tracker){
+ DebugAccelF("(dix prtacc) query: last tracker in effect\n");
+ i = vel->num_tracker-1;
+ }
+ if(i>=0){
+ n = TRACKER_INDEX(vel, i);
+ DebugAccelF("(dix prtacc) result: offset %i [dx: %i dy: %i diff: %i]\n",
+ i,
+ vel->tracker[n].dx,
+ vel->tracker[n].dy,
+ cur_t - vel->tracker[n].time);
+ }
+ return res;
+}
+
+#undef TRACKER_INDEX
+
+/**
+ * Perform velocity approximation based on 2D 'mickeys' (mouse motion delta).
+ * return true if non-visible state reset is suggested
+ */
+short
+ProcessVelocityData2D(
+ DeviceVelocityPtr vel,
+ int dx,
+ int dy,
+ int time)
+{
+ float velocity;
+
+ vel->last_velocity = vel->velocity;
+
+ FeedTrackers(vel, dx, dy, time);
+
+ velocity = QueryTrackers(vel, time);
+
+ vel->velocity = velocity;
+ return velocity == 0;
+}
+
+/**
+ * this flattens significant ( > 1) mickeys a little bit for more steady
+ * constant-velocity response
+ */
+static inline float
+ApplySimpleSoftening(int od, int d)
+{
+ float res = d;
+ if (d <= 1 && d >= -1)
+ return res;
+ if (d > od)
+ res -= 0.5;
+ else if (d < od)
+ res += 0.5;
+ return res;
+}
+
+
+static void
+ApplySofteningAndConstantDeceleration(
+ DeviceVelocityPtr vel,
+ int dx,
+ int dy,
+ float* fdx,
+ float* fdy,
+ short do_soften)
+{
+ if (do_soften && vel->use_softening) {
+ *fdx = ApplySimpleSoftening(vel->last_dx, dx);
+ *fdy = ApplySimpleSoftening(vel->last_dy, dy);
+ } else {
+ *fdx = dx;
+ *fdy = dy;
+ }
+
+ *fdx *= vel->const_acceleration;
+ *fdy *= vel->const_acceleration;
+}
+
+/*
+ * compute the acceleration for given velocity and enforce min_acceleartion
+ */
+float
+BasicComputeAcceleration(
+ DeviceIntPtr dev,
+ DeviceVelocityPtr vel,
+ float velocity,
+ float threshold,
+ float acc){
+
+ float result;
+ result = vel->Profile(dev, vel, velocity, threshold, acc);
+
+ /* enforce min_acceleration */
+ if (result < vel->min_acceleration)
+ result = vel->min_acceleration;
+ return result;
+}
+
+/**
+ * Compute acceleration. Takes into account averaging, nv-reset, etc.
+ */
+static float
+ComputeAcceleration(
+ DeviceIntPtr dev,
+ DeviceVelocityPtr vel,
+ float threshold,
+ float acc){
+ float res;
+
+ if(vel->velocity <= 0){
+ DebugAccelF("(dix ptracc) profile skipped\n");
+ /*
+ * If we have no idea about device velocity, don't pretend it.
+ */
+ return 1;
+ }
+
+ if(vel->average_accel && vel->velocity != vel->last_velocity){
+ /* use simpson's rule to average acceleration between
+ * current and previous velocity.
+ * Though being the more natural choice, it causes a minor delay
+ * in comparison, so it can be disabled. */
+ res = BasicComputeAcceleration(
+ dev, vel, vel->velocity, threshold, acc);
+ res += BasicComputeAcceleration(
+ dev, vel, vel->last_velocity, threshold, acc);
+ res += 4.0f * BasicComputeAcceleration(dev, vel,
+ (vel->last_velocity + vel->velocity) / 2,
+ threshold, acc);
+ res /= 6.0f;
+ DebugAccelF("(dix ptracc) profile average [%.2f ... %.2f] is %.3f\n",
+ vel->velocity, vel->last_velocity, res);
+ return res;
+ }else{
+ res = BasicComputeAcceleration(dev, vel,
+ vel->velocity, threshold, acc);
+ DebugAccelF("(dix ptracc) profile sample [%.2f] is %.3f\n",
+ vel->velocity, res);
+ return res;
+ }
+}
+
+
+/*****************************************
+ * Acceleration functions and profiles
+ ****************************************/
+
+/**
+ * Polynomial function similar previous one, but with f(1) = 1
+ */
+static float
+PolynomialAccelerationProfile(
+ DeviceIntPtr dev,
+ DeviceVelocityPtr vel,
+ float velocity,
+ float ignored,
+ float acc)
+{
+ return pow(velocity, (acc - 1.0) * 0.5);
+}
+
+
+/**
+ * returns acceleration for velocity.
+ * This profile selects the two functions like the old scheme did
+ */
+static float
+ClassicProfile(
+ DeviceIntPtr dev,
+ DeviceVelocityPtr vel,
+ float velocity,
+ float threshold,
+ float acc)
+{
+ if (threshold > 0) {
+ return SimpleSmoothProfile (dev,
+ vel,
+ velocity,
+ threshold,
+ acc);
+ } else {
+ return PolynomialAccelerationProfile (dev,
+ vel,
+ velocity,
+ 0,
+ acc);
+ }
+}
+
+
+/**
+ * Power profile
+ * This has a completely smooth transition curve, i.e. no jumps in the
+ * derivatives.
+ *
+ * This has the expense of overall response dependency on min-acceleration.
+ * In effect, min_acceleration mimics const_acceleration in this profile.
+ */
+static float
+PowerProfile(
+ DeviceIntPtr dev,
+ DeviceVelocityPtr vel,
+ float velocity,
+ float threshold,
+ float acc)
+{
+ float vel_dist;
+
+ acc = (acc-1.0) * 0.1f + 1.0; /* without this, acc of 2 is unuseable */
+
+ if (velocity <= threshold)
+ return vel->min_acceleration;
+ vel_dist = velocity - threshold;
+ return (pow(acc, vel_dist)) * vel->min_acceleration;
+}
+
+
+/**
+ * just a smooth function in [0..1] -> [0..1]
+ * - point symmetry at 0.5
+ * - f'(0) = f'(1) = 0
+ * - starts faster than a sinoid
+ * - smoothness C1 (Cinf if you dare to ignore endpoints)
+ */
+static inline float
+CalcPenumbralGradient(float x){
+ x *= 2.0f;
+ x -= 1.0f;
+ return 0.5f + (x * sqrt(1.0f - x*x) + asin(x))/M_PI;
+}
+
+
+/**
+ * acceleration function similar to classic accelerated/unaccelerated,
+ * but with smooth transition in between (and towards zero for adaptive dec.).
+ */
+static float
+SimpleSmoothProfile(
+ DeviceIntPtr dev,
+ DeviceVelocityPtr vel,
+ float velocity,
+ float threshold,
+ float acc)
+{
+ if(velocity < 1.0f)
+ return CalcPenumbralGradient(0.5 + velocity*0.5) * 2.0f - 1.0f;
+ if(threshold < 1.0f)
+ threshold = 1.0f;
+ if (velocity <= threshold)
+ return 1;
+ velocity /= threshold;
+ if (velocity >= acc)
+ return acc;
+ else
+ return 1.0f + (CalcPenumbralGradient(velocity/acc) * (acc - 1.0f));
+}
+
+
+/**
+ * This profile uses the first half of the penumbral gradient as a start
+ * and then scales linearly.
+ */
+static float
+SmoothLinearProfile(
+ DeviceIntPtr dev,
+ DeviceVelocityPtr vel,
+ float velocity,
+ float threshold,
+ float acc)
+{
+ float res, nv;
+
+ if(acc > 1.0f)
+ acc -= 1.0f; /*this is so acc = 1 is no acceleration */
+ else
+ return 1.0f;
+
+ nv = (velocity - threshold) * acc * 0.5f;
+
+ if(nv < 0){
+ res = 0;
+ }else if(nv < 2){
+ res = CalcPenumbralGradient(nv*0.25f)*2.0f;
+ }else{
+ nv -= 2.0f;
+ res = nv * 2.0f / M_PI /* steepness of gradient at 0.5 */
+ + 1.0f; /* gradient crosses 2|1 */
+ }
+ res += vel->min_acceleration;
+ return res;
+}
+
+
+/**
+ * From 0 to threshold, the response graduates smoothly from min_accel to
+ * acceleration. Beyond threshold it is exactly the specified acceleration.
+ */
+static float
+SmoothLimitedProfile(
+ DeviceIntPtr dev,
+ DeviceVelocityPtr vel,
+ float velocity,
+ float threshold,
+ float acc)
+{
+ float res;
+
+ if(velocity >= threshold || threshold == 0.0f)
+ return acc;
+
+ velocity /= threshold; /* should be [0..1[ now */
+
+ res = CalcPenumbralGradient(velocity) * (acc - vel->min_acceleration);
+
+ return vel->min_acceleration + res;
+}
+
+
+static float
+LinearProfile(
+ DeviceIntPtr dev,
+ DeviceVelocityPtr vel,
+ float velocity,
+ float threshold,
+ float acc)
+{
+ return acc * velocity;
+}
+
+static float
+NoProfile(
+ DeviceIntPtr dev,
+ DeviceVelocityPtr vel,
+ float velocity,
+ float threshold,
+ float acc)
+{
+ return 1.0f;
+}
+
+static PointerAccelerationProfileFunc
+GetAccelerationProfile(
+ DeviceVelocityPtr vel,
+ int profile_num)
+{
+ switch(profile_num){
+ case AccelProfileClassic:
+ return ClassicProfile;
+ case AccelProfileDeviceSpecific:
+ return vel->deviceSpecificProfile;
+ case AccelProfilePolynomial:
+ return PolynomialAccelerationProfile;
+ case AccelProfileSmoothLinear:
+ return SmoothLinearProfile;
+ case AccelProfileSimple:
+ return SimpleSmoothProfile;
+ case AccelProfilePower:
+ return PowerProfile;
+ case AccelProfileLinear:
+ return LinearProfile;
+ case AccelProfileSmoothLimited:
+ return SmoothLimitedProfile;
+ case AccelProfileNone:
+ return NoProfile;
+ default:
+ return NULL;
+ }
+}
+
+/**
+ * Set the profile by number.
+ * Intended to make profiles exchangeable at runtime.
+ * If you created a profile, give it a number here and in the header to
+ * make it selectable. In case some profile-specific init is needed, here
+ * would be a good place, since FreeVelocityData() also calls this with
+ * PROFILE_UNINITIALIZE.
+ *
+ * returns FALSE if profile number is unavailable, TRUE otherwise.
+ */
+int
+SetAccelerationProfile(
+ DeviceVelocityPtr vel,
+ int profile_num)
+{
+ PointerAccelerationProfileFunc profile;
+ profile = GetAccelerationProfile(vel, profile_num);
+
+ if(profile == NULL && profile_num != PROFILE_UNINITIALIZE)
+ return FALSE;
+
+ /* Here one could free old profile-private data */
+ free(vel->profile_private);
+ vel->profile_private = NULL;
+ /* Here one could init profile-private data */
+ vel->Profile = profile;
+ vel->statistics.profile_number = profile_num;
+ return TRUE;
+}
+
+/**********************************************
+ * driver interaction
+ **********************************************/
+
+
+/**
+ * device-specific profile
+ *
+ * The device-specific profile is intended as a hook for a driver
+ * which may want to provide an own acceleration profile.
+ * It should not rely on profile-private data, instead
+ * it should do init/uninit in the driver (ie. with DEVICE_INIT and friends).
+ * Users may override or choose it.
+ */
+void
+SetDeviceSpecificAccelerationProfile(
+ DeviceVelocityPtr vel,
+ PointerAccelerationProfileFunc profile)
+{
+ if(vel)
+ vel->deviceSpecificProfile = profile;
+}
+
+/**
+ * Use this function to obtain a DeviceVelocityPtr for a device. Will return NULL if
+ * the predictable acceleration scheme is not in effect.
+ */
+DeviceVelocityPtr
+GetDevicePredictableAccelData(
+ DeviceIntPtr dev)
+{
+ /*sanity check*/
+ if(!dev){
+ ErrorF("[dix] accel: DeviceIntPtr was NULL");
+ return NULL;
+ }
+ if( dev->valuator &&
+ dev->valuator->accelScheme.AccelSchemeProc ==
+ acceleratePointerPredictable &&
+ dev->valuator->accelScheme.accelData != NULL){
+
+ return (DeviceVelocityPtr)dev->valuator->accelScheme.accelData;
+ }
+ return NULL;
+}
+
+/********************************
+ * acceleration schemes
+ *******************************/
+
+/**
+ * Modifies valuators in-place.
+ * This version employs a velocity approximation algorithm to
+ * enable fine-grained predictable acceleration profiles.
+ */
+void
+acceleratePointerPredictable(
+ DeviceIntPtr dev,
+ int first_valuator,
+ int num_valuators,
+ int *valuators,
+ int evtime)
+{
+ float fdx, fdy, tmp, mult; /* no need to init */
+ int dx = 0, dy = 0;
+ int *px = NULL, *py = NULL;
+ DeviceVelocityPtr velocitydata = GetDevicePredictableAccelData(dev);
+ Bool soften = TRUE;
+
+ if (!num_valuators || !valuators || !velocitydata)
+ return;
+
+ if (velocitydata->statistics.profile_number == AccelProfileNone &&
+ velocitydata->const_acceleration == 1.0f) {
+ return; /*we're inactive anyway, so skip the whole thing.*/
+ }
+
+ if (first_valuator == 0) {
+ dx = valuators[0];
+ px = &valuators[0];
+ }
+ if (first_valuator <= 1 && num_valuators >= (2 - first_valuator)) {
+ dy = valuators[1 - first_valuator];
+ py = &valuators[1 - first_valuator];
+ }
+
+ if (dx || dy){
+ /* reset non-visible state? */
+ if (ProcessVelocityData2D(velocitydata, dx , dy, evtime)) {
+ soften = FALSE;
+ }
+
+ if (dev->ptrfeed && dev->ptrfeed->ctrl.num) {
+ /* invoke acceleration profile to determine acceleration */
+ mult = ComputeAcceleration (dev, velocitydata,
+ dev->ptrfeed->ctrl.threshold,
+ (float)dev->ptrfeed->ctrl.num /
+ (float)dev->ptrfeed->ctrl.den);
+
+ if(mult != 1.0f || velocitydata->const_acceleration != 1.0f) {
+ ApplySofteningAndConstantDeceleration( velocitydata,
+ dx, dy,
+ &fdx, &fdy,
+ (mult > 1.0f) && soften);
+
+ if (dx) {
+ tmp = mult * fdx + dev->last.remainder[0];
+ /* Since it may not be apparent: lrintf() does not offer
+ * strong statements about rounding; however because we
+ * process each axis conditionally, there's no danger
+ * of a toggling remainder. Its lack of guarantees likely
+ * makes it faster on the average target. */
+ *px = lrintf(tmp);
+ dev->last.remainder[0] = tmp - (float)*px;
+ }
+ if (dy) {
+ tmp = mult * fdy + dev->last.remainder[1];
+ *py = lrintf(tmp);
+ dev->last.remainder[1] = tmp - (float)*py;
+ }
+ DebugAccelF("pos (%i | %i) remainders x: %.3f y: %.3f delta x:%.3f y:%.3f\n",
+ *px, *py, dev->last.remainder[0], dev->last.remainder[1], fdx, fdy);
+ }
+ }
+ }
+ /* remember last motion delta (for softening/slow movement treatment) */
+ velocitydata->last_dx = dx;
+ velocitydata->last_dy = dy;
+}
+
+
+
+/**
+ * Originally a part of xf86PostMotionEvent; modifies valuators
+ * in-place. Retained mostly for embedded scenarios.
+ */
+void
+acceleratePointerLightweight(
+ DeviceIntPtr dev,
+ int first_valuator,
+ int num_valuators,
+ int *valuators,
+ int ignored)
+{
+ float mult = 0.0;
+ int dx = 0, dy = 0;
+ int *px = NULL, *py = NULL;
+
+ if (!num_valuators || !valuators)
+ return;
+
+ if (first_valuator == 0) {
+ dx = valuators[0];
+ px = &valuators[0];
+ }
+ if (first_valuator <= 1 && num_valuators >= (2 - first_valuator)) {
+ dy = valuators[1 - first_valuator];
+ py = &valuators[1 - first_valuator];
+ }
+
+ if (!dx && !dy)
+ return;
+
+ if (dev->ptrfeed && dev->ptrfeed->ctrl.num) {
+ /* modeled from xf86Events.c */
+ if (dev->ptrfeed->ctrl.threshold) {
+ if ((abs(dx) + abs(dy)) >= dev->ptrfeed->ctrl.threshold) {
+ dev->last.remainder[0] = ((float)dx *
+ (float)(dev->ptrfeed->ctrl.num)) /
+ (float)(dev->ptrfeed->ctrl.den) +
+ dev->last.remainder[0];
+ if (px) {
+ *px = (int)dev->last.remainder[0];
+ dev->last.remainder[0] = dev->last.remainder[0] -
+ (float)(*px);
+ }
+
+ dev->last.remainder[1] = ((float)dy *
+ (float)(dev->ptrfeed->ctrl.num)) /
+ (float)(dev->ptrfeed->ctrl.den) +
+ dev->last.remainder[1];
+ if (py) {
+ *py = (int)dev->last.remainder[1];
+ dev->last.remainder[1] = dev->last.remainder[1] -
+ (float)(*py);
+ }
+ }
+ }
+ else {
+ mult = pow((float)dx * (float)dx + (float)dy * (float)dy,
+ ((float)(dev->ptrfeed->ctrl.num) /
+ (float)(dev->ptrfeed->ctrl.den) - 1.0) /
+ 2.0) / 2.0;
+ if (dx) {
+ dev->last.remainder[0] = mult * (float)dx +
+ dev->last.remainder[0];
+ *px = (int)dev->last.remainder[0];
+ dev->last.remainder[0] = dev->last.remainder[0] -
+ (float)(*px);
+ }
+ if (dy) {
+ dev->last.remainder[1] = mult * (float)dy +
+ dev->last.remainder[1];
+ *py = (int)dev->last.remainder[1];
+ dev->last.remainder[1] = dev->last.remainder[1] -
+ (float)(*py);
+ }
+ }
+ }
+}