diff options
Diffstat (limited to 'mesalib/src/mesa/main/buffers.c')
-rw-r--r-- | mesalib/src/mesa/main/buffers.c | 1068 |
1 files changed, 542 insertions, 526 deletions
diff --git a/mesalib/src/mesa/main/buffers.c b/mesalib/src/mesa/main/buffers.c index 928450f0f..63f53e2b0 100644 --- a/mesalib/src/mesa/main/buffers.c +++ b/mesalib/src/mesa/main/buffers.c @@ -1,526 +1,542 @@ -/*
- * Mesa 3-D graphics library
- * Version: 7.1
- *
- * Copyright (C) 1999-2007 Brian Paul All Rights Reserved.
- *
- * 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 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
- * BRIAN PAUL 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.
- */
-
-
-/**
- * \file buffers.c
- * glReadBuffer, DrawBuffer functions.
- */
-
-
-
-#include "glheader.h"
-#include "buffers.h"
-#include "colormac.h"
-#include "context.h"
-#include "enums.h"
-#include "mtypes.h"
-
-
-#define BAD_MASK ~0u
-
-
-/**
- * Return bitmask of BUFFER_BIT_* flags indicating which color buffers are
- * available to the rendering context (for drawing or reading).
- * This depends on the type of framebuffer. For window system framebuffers
- * we look at the framebuffer's visual. But for user-create framebuffers we
- * look at the number of supported color attachments.
- * \param fb the framebuffer to draw to, or read from
- * \return bitmask of BUFFER_BIT_* flags
- */
-static GLbitfield
-supported_buffer_bitmask(const struct gl_context *ctx, const struct gl_framebuffer *fb)
-{
- GLbitfield mask = 0x0;
-
- if (fb->Name > 0) {
- /* A user-created renderbuffer */
- GLuint i;
- ASSERT(ctx->Extensions.EXT_framebuffer_object);
- for (i = 0; i < ctx->Const.MaxColorAttachments; i++) {
- mask |= (BUFFER_BIT_COLOR0 << i);
- }
- }
- else {
- /* A window system framebuffer */
- GLint i;
- mask = BUFFER_BIT_FRONT_LEFT; /* always have this */
- if (fb->Visual.stereoMode) {
- mask |= BUFFER_BIT_FRONT_RIGHT;
- if (fb->Visual.doubleBufferMode) {
- mask |= BUFFER_BIT_BACK_LEFT | BUFFER_BIT_BACK_RIGHT;
- }
- }
- else if (fb->Visual.doubleBufferMode) {
- mask |= BUFFER_BIT_BACK_LEFT;
- }
-
- for (i = 0; i < fb->Visual.numAuxBuffers; i++) {
- mask |= (BUFFER_BIT_AUX0 << i);
- }
- }
-
- return mask;
-}
-
-
-/**
- * Helper routine used by glDrawBuffer and glDrawBuffersARB.
- * Given a GLenum naming one or more color buffers (such as
- * GL_FRONT_AND_BACK), return the corresponding bitmask of BUFFER_BIT_* flags.
- */
-static GLbitfield
-draw_buffer_enum_to_bitmask(GLenum buffer)
-{
- switch (buffer) {
- case GL_NONE:
- return 0;
- case GL_FRONT:
- return BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_FRONT_RIGHT;
- case GL_BACK:
- return BUFFER_BIT_BACK_LEFT | BUFFER_BIT_BACK_RIGHT;
- case GL_RIGHT:
- return BUFFER_BIT_FRONT_RIGHT | BUFFER_BIT_BACK_RIGHT;
- case GL_FRONT_RIGHT:
- return BUFFER_BIT_FRONT_RIGHT;
- case GL_BACK_RIGHT:
- return BUFFER_BIT_BACK_RIGHT;
- case GL_BACK_LEFT:
- return BUFFER_BIT_BACK_LEFT;
- case GL_FRONT_AND_BACK:
- return BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_BACK_LEFT
- | BUFFER_BIT_FRONT_RIGHT | BUFFER_BIT_BACK_RIGHT;
- case GL_LEFT:
- return BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_BACK_LEFT;
- case GL_FRONT_LEFT:
- return BUFFER_BIT_FRONT_LEFT;
- case GL_AUX0:
- return BUFFER_BIT_AUX0;
- case GL_AUX1:
- case GL_AUX2:
- case GL_AUX3:
- return 1 << BUFFER_COUNT; /* invalid, but not BAD_MASK */
- case GL_COLOR_ATTACHMENT0_EXT:
- return BUFFER_BIT_COLOR0;
- case GL_COLOR_ATTACHMENT1_EXT:
- return BUFFER_BIT_COLOR1;
- case GL_COLOR_ATTACHMENT2_EXT:
- return BUFFER_BIT_COLOR2;
- case GL_COLOR_ATTACHMENT3_EXT:
- return BUFFER_BIT_COLOR3;
- case GL_COLOR_ATTACHMENT4_EXT:
- return BUFFER_BIT_COLOR4;
- case GL_COLOR_ATTACHMENT5_EXT:
- return BUFFER_BIT_COLOR5;
- case GL_COLOR_ATTACHMENT6_EXT:
- return BUFFER_BIT_COLOR6;
- case GL_COLOR_ATTACHMENT7_EXT:
- return BUFFER_BIT_COLOR7;
- default:
- /* error */
- return BAD_MASK;
- }
-}
-
-
-/**
- * Helper routine used by glReadBuffer.
- * Given a GLenum naming a color buffer, return the index of the corresponding
- * renderbuffer (a BUFFER_* value).
- * return -1 for an invalid buffer.
- */
-static GLint
-read_buffer_enum_to_index(GLenum buffer)
-{
- switch (buffer) {
- case GL_FRONT:
- return BUFFER_FRONT_LEFT;
- case GL_BACK:
- return BUFFER_BACK_LEFT;
- case GL_RIGHT:
- return BUFFER_FRONT_RIGHT;
- case GL_FRONT_RIGHT:
- return BUFFER_FRONT_RIGHT;
- case GL_BACK_RIGHT:
- return BUFFER_BACK_RIGHT;
- case GL_BACK_LEFT:
- return BUFFER_BACK_LEFT;
- case GL_LEFT:
- return BUFFER_FRONT_LEFT;
- case GL_FRONT_LEFT:
- return BUFFER_FRONT_LEFT;
- case GL_AUX0:
- return BUFFER_AUX0;
- case GL_AUX1:
- case GL_AUX2:
- case GL_AUX3:
- return BUFFER_COUNT; /* invalid, but not -1 */
- case GL_COLOR_ATTACHMENT0_EXT:
- return BUFFER_COLOR0;
- case GL_COLOR_ATTACHMENT1_EXT:
- return BUFFER_COLOR1;
- case GL_COLOR_ATTACHMENT2_EXT:
- return BUFFER_COLOR2;
- case GL_COLOR_ATTACHMENT3_EXT:
- return BUFFER_COLOR3;
- case GL_COLOR_ATTACHMENT4_EXT:
- return BUFFER_COLOR4;
- case GL_COLOR_ATTACHMENT5_EXT:
- return BUFFER_COLOR5;
- case GL_COLOR_ATTACHMENT6_EXT:
- return BUFFER_COLOR6;
- case GL_COLOR_ATTACHMENT7_EXT:
- return BUFFER_COLOR7;
- default:
- /* error */
- return -1;
- }
-}
-
-
-/**
- * Called by glDrawBuffer().
- * Specify which renderbuffer(s) to draw into for the first color output.
- * <buffer> can name zero, one, two or four renderbuffers!
- * \sa _mesa_DrawBuffersARB
- *
- * \param buffer buffer token such as GL_LEFT or GL_FRONT_AND_BACK, etc.
- *
- * Note that the behaviour of this function depends on whether the
- * current ctx->DrawBuffer is a window-system framebuffer (Name=0) or
- * a user-created framebuffer object (Name!=0).
- * In the former case, we update the per-context ctx->Color.DrawBuffer
- * state var _and_ the FB's ColorDrawBuffer state.
- * In the later case, we update the FB's ColorDrawBuffer state only.
- *
- * Furthermore, upon a MakeCurrent() or BindFramebuffer() call, if the
- * new FB is a window system FB, we need to re-update the FB's
- * ColorDrawBuffer state to match the context. This is handled in
- * _mesa_update_framebuffer().
- *
- * See the GL_EXT_framebuffer_object spec for more info.
- */
-void GLAPIENTRY
-_mesa_DrawBuffer(GLenum buffer)
-{
- GLbitfield destMask;
- GET_CURRENT_CONTEXT(ctx);
- ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx); /* too complex... */
-
- if (MESA_VERBOSE & VERBOSE_API) {
- _mesa_debug(ctx, "glDrawBuffer %s\n", _mesa_lookup_enum_by_nr(buffer));
- }
-
- if (buffer == GL_NONE) {
- destMask = 0x0;
- }
- else {
- const GLbitfield supportedMask
- = supported_buffer_bitmask(ctx, ctx->DrawBuffer);
- destMask = draw_buffer_enum_to_bitmask(buffer);
- if (destMask == BAD_MASK) {
- /* totally bogus buffer */
- _mesa_error(ctx, GL_INVALID_ENUM, "glDrawBuffer(buffer=0x%x)", buffer);
- return;
- }
- destMask &= supportedMask;
- if (destMask == 0x0) {
- /* none of the named color buffers exist! */
- _mesa_error(ctx, GL_INVALID_OPERATION,
- "glDrawBuffer(buffer=0x%x)", buffer);
- return;
- }
- }
-
- /* if we get here, there's no error so set new state */
- _mesa_drawbuffers(ctx, 1, &buffer, &destMask);
-
- /*
- * Call device driver function.
- */
- if (ctx->Driver.DrawBuffers)
- ctx->Driver.DrawBuffers(ctx, 1, &buffer);
- else if (ctx->Driver.DrawBuffer)
- ctx->Driver.DrawBuffer(ctx, buffer);
-}
-
-
-/**
- * Called by glDrawBuffersARB; specifies the destination color renderbuffers
- * for N fragment program color outputs.
- * \sa _mesa_DrawBuffer
- * \param n number of outputs
- * \param buffers array [n] of renderbuffer names. Unlike glDrawBuffer, the
- * names cannot specify more than one buffer. For example,
- * GL_FRONT_AND_BACK is illegal.
- */
-void GLAPIENTRY
-_mesa_DrawBuffersARB(GLsizei n, const GLenum *buffers)
-{
- GLint output;
- GLbitfield usedBufferMask, supportedMask;
- GLbitfield destMask[MAX_DRAW_BUFFERS];
- GET_CURRENT_CONTEXT(ctx);
- ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
-
- /* Turns out n==0 is a valid input that should not produce an error.
- * The remaining code below correctly handles the n==0 case.
- */
- if (n < 0 || n > (GLsizei) ctx->Const.MaxDrawBuffers) {
- _mesa_error(ctx, GL_INVALID_VALUE, "glDrawBuffersARB(n)");
- return;
- }
-
- supportedMask = supported_buffer_bitmask(ctx, ctx->DrawBuffer);
- usedBufferMask = 0x0;
-
- /* complicated error checking... */
- for (output = 0; output < n; output++) {
- if (buffers[output] == GL_NONE) {
- destMask[output] = 0x0;
- }
- else {
- destMask[output] = draw_buffer_enum_to_bitmask(buffers[output]);
- if (destMask[output] == BAD_MASK
- || _mesa_bitcount(destMask[output]) > 1) {
- _mesa_error(ctx, GL_INVALID_ENUM, "glDrawBuffersARB(buffer)");
- return;
- }
- destMask[output] &= supportedMask;
- if (destMask[output] == 0) {
- _mesa_error(ctx, GL_INVALID_OPERATION,
- "glDrawBuffersARB(unsupported buffer)");
- return;
- }
- if (destMask[output] & usedBufferMask) {
- /* can't specify a dest buffer more than once! */
- _mesa_error(ctx, GL_INVALID_OPERATION,
- "glDrawBuffersARB(duplicated buffer)");
- return;
- }
-
- /* update bitmask */
- usedBufferMask |= destMask[output];
- }
- }
-
- /* OK, if we get here, there were no errors so set the new state */
- _mesa_drawbuffers(ctx, n, buffers, destMask);
-
- /*
- * Call device driver function. Note that n can be equal to 0,
- * in which case we don't want to reference buffers[0], which
- * may not be valid.
- */
- if (ctx->Driver.DrawBuffers)
- ctx->Driver.DrawBuffers(ctx, n, buffers);
- else if (ctx->Driver.DrawBuffer)
- ctx->Driver.DrawBuffer(ctx, n > 0 ? buffers[0] : GL_NONE);
-}
-
-
-/**
- * Helper function to set the GL_DRAW_BUFFER state in the context and
- * current FBO. Called via glDrawBuffer(), glDrawBuffersARB()
- *
- * All error checking will have been done prior to calling this function
- * so nothing should go wrong at this point.
- *
- * \param ctx current context
- * \param n number of color outputs to set
- * \param buffers array[n] of colorbuffer names, like GL_LEFT.
- * \param destMask array[n] of BUFFER_BIT_* bitmasks which correspond to the
- * colorbuffer names. (i.e. GL_FRONT_AND_BACK =>
- * BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_BACK_LEFT).
- */
-void
-_mesa_drawbuffers(struct gl_context *ctx, GLuint n, const GLenum *buffers,
- const GLbitfield *destMask)
-{
- struct gl_framebuffer *fb = ctx->DrawBuffer;
- GLbitfield mask[MAX_DRAW_BUFFERS];
- GLboolean newState = GL_FALSE;
-
- if (!destMask) {
- /* compute destMask values now */
- const GLbitfield supportedMask = supported_buffer_bitmask(ctx, fb);
- GLuint output;
- for (output = 0; output < n; output++) {
- mask[output] = draw_buffer_enum_to_bitmask(buffers[output]);
- ASSERT(mask[output] != BAD_MASK);
- mask[output] &= supportedMask;
- }
- destMask = mask;
- }
-
- /*
- * If n==1, destMask[0] may have up to four bits set.
- * Otherwise, destMask[x] can only have one bit set.
- */
- if (n == 1) {
- GLuint count = 0, destMask0 = destMask[0];
- while (destMask0) {
- GLint bufIndex = _mesa_ffs(destMask0) - 1;
- if (fb->_ColorDrawBufferIndexes[count] != bufIndex) {
- fb->_ColorDrawBufferIndexes[count] = bufIndex;
- newState = GL_TRUE;
- }
- count++;
- destMask0 &= ~(1 << bufIndex);
- }
- fb->ColorDrawBuffer[0] = buffers[0];
- if (fb->_NumColorDrawBuffers != count) {
- fb->_NumColorDrawBuffers = count;
- newState = GL_TRUE;
- }
- }
- else {
- GLuint buf, count = 0;
- for (buf = 0; buf < n; buf++ ) {
- if (destMask[buf]) {
- GLint bufIndex = _mesa_ffs(destMask[buf]) - 1;
- /* only one bit should be set in the destMask[buf] field */
- ASSERT(_mesa_bitcount(destMask[buf]) == 1);
- if (fb->_ColorDrawBufferIndexes[buf] != bufIndex) {
- fb->_ColorDrawBufferIndexes[buf] = bufIndex;
- newState = GL_TRUE;
- }
- count = buf + 1;
- }
- else {
- if (fb->_ColorDrawBufferIndexes[buf] != -1) {
- fb->_ColorDrawBufferIndexes[buf] = -1;
- newState = GL_TRUE;
- }
- }
- fb->ColorDrawBuffer[buf] = buffers[buf];
- }
- /* set remaining outputs to -1 (GL_NONE) */
- while (buf < ctx->Const.MaxDrawBuffers) {
- if (fb->_ColorDrawBufferIndexes[buf] != -1) {
- fb->_ColorDrawBufferIndexes[buf] = -1;
- newState = GL_TRUE;
- }
- fb->ColorDrawBuffer[buf] = GL_NONE;
- buf++;
- }
- fb->_NumColorDrawBuffers = count;
- }
-
- if (fb->Name == 0) {
- /* also set context drawbuffer state */
- GLuint buf;
- for (buf = 0; buf < ctx->Const.MaxDrawBuffers; buf++) {
- if (ctx->Color.DrawBuffer[buf] != fb->ColorDrawBuffer[buf]) {
- ctx->Color.DrawBuffer[buf] = fb->ColorDrawBuffer[buf];
- newState = GL_TRUE;
- }
- }
- }
-
- if (newState)
- FLUSH_VERTICES(ctx, _NEW_BUFFERS);
-}
-
-
-/**
- * Like \sa _mesa_drawbuffers(), this is a helper function for setting
- * GL_READ_BUFFER state in the context and current FBO.
- * \param ctx the rendering context
- * \param buffer GL_FRONT, GL_BACK, GL_COLOR_ATTACHMENT0, etc.
- * \param bufferIndex the numerical index corresponding to 'buffer'
- */
-void
-_mesa_readbuffer(struct gl_context *ctx, GLenum buffer, GLint bufferIndex)
-{
- struct gl_framebuffer *fb = ctx->ReadBuffer;
-
- if (fb->Name == 0) {
- /* Only update the per-context READ_BUFFER state if we're bound to
- * a window-system framebuffer.
- */
- ctx->Pixel.ReadBuffer = buffer;
- }
-
- fb->ColorReadBuffer = buffer;
- fb->_ColorReadBufferIndex = bufferIndex;
-
- ctx->NewState |= _NEW_BUFFERS;
-}
-
-
-
-/**
- * Called by glReadBuffer to set the source renderbuffer for reading pixels.
- * \param mode color buffer such as GL_FRONT, GL_BACK, etc.
- */
-void GLAPIENTRY
-_mesa_ReadBuffer(GLenum buffer)
-{
- struct gl_framebuffer *fb;
- GLbitfield supportedMask;
- GLint srcBuffer;
- GET_CURRENT_CONTEXT(ctx);
- ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx);
-
- if (MESA_VERBOSE & VERBOSE_API)
- _mesa_debug(ctx, "glReadBuffer %s\n", _mesa_lookup_enum_by_nr(buffer));
-
- fb = ctx->ReadBuffer;
-
- if (MESA_VERBOSE & VERBOSE_API)
- _mesa_debug(ctx, "glReadBuffer %s\n", _mesa_lookup_enum_by_nr(buffer));
-
- if (fb->Name > 0 && buffer == GL_NONE) {
- /* This is legal for user-created framebuffer objects */
- srcBuffer = -1;
- }
- else {
- /* general case / window-system framebuffer */
- srcBuffer = read_buffer_enum_to_index(buffer);
- if (srcBuffer == -1) {
- _mesa_error(ctx, GL_INVALID_ENUM,
- "glReadBuffer(buffer=0x%x)", buffer);
- return;
- }
- supportedMask = supported_buffer_bitmask(ctx, fb);
- if (((1 << srcBuffer) & supportedMask) == 0) {
- _mesa_error(ctx, GL_INVALID_OPERATION,
- "glReadBuffer(buffer=0x%x)", buffer);
- return;
- }
- }
-
- /* OK, all error checking has been completed now */
-
- _mesa_readbuffer(ctx, buffer, srcBuffer);
- ctx->NewState |= _NEW_BUFFERS;
-
- /*
- * Call device driver function.
- */
- if (ctx->Driver.ReadBuffer)
- (*ctx->Driver.ReadBuffer)(ctx, buffer);
-}
+/* + * Mesa 3-D graphics library + * Version: 7.1 + * + * Copyright (C) 1999-2007 Brian Paul All Rights Reserved. + * + * 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 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 + * BRIAN PAUL 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. + */ + + +/** + * \file buffers.c + * glReadBuffer, DrawBuffer functions. + */ + + + +#include "glheader.h" +#include "buffers.h" +#include "colormac.h" +#include "context.h" +#include "enums.h" +#include "mtypes.h" + + +#define BAD_MASK ~0u + + +/** + * Return bitmask of BUFFER_BIT_* flags indicating which color buffers are + * available to the rendering context (for drawing or reading). + * This depends on the type of framebuffer. For window system framebuffers + * we look at the framebuffer's visual. But for user-create framebuffers we + * look at the number of supported color attachments. + * \param fb the framebuffer to draw to, or read from + * \return bitmask of BUFFER_BIT_* flags + */ +static GLbitfield +supported_buffer_bitmask(const struct gl_context *ctx, const struct gl_framebuffer *fb) +{ + GLbitfield mask = 0x0; + + if (fb->Name > 0) { + /* A user-created renderbuffer */ + GLuint i; + ASSERT(ctx->Extensions.EXT_framebuffer_object); + for (i = 0; i < ctx->Const.MaxColorAttachments; i++) { + mask |= (BUFFER_BIT_COLOR0 << i); + } + } + else { + /* A window system framebuffer */ + GLint i; + mask = BUFFER_BIT_FRONT_LEFT; /* always have this */ + if (fb->Visual.stereoMode) { + mask |= BUFFER_BIT_FRONT_RIGHT; + if (fb->Visual.doubleBufferMode) { + mask |= BUFFER_BIT_BACK_LEFT | BUFFER_BIT_BACK_RIGHT; + } + } + else if (fb->Visual.doubleBufferMode) { + mask |= BUFFER_BIT_BACK_LEFT; + } + + for (i = 0; i < fb->Visual.numAuxBuffers; i++) { + mask |= (BUFFER_BIT_AUX0 << i); + } + } + + return mask; +} + + +/** + * Helper routine used by glDrawBuffer and glDrawBuffersARB. + * Given a GLenum naming one or more color buffers (such as + * GL_FRONT_AND_BACK), return the corresponding bitmask of BUFFER_BIT_* flags. + */ +static GLbitfield +draw_buffer_enum_to_bitmask(GLenum buffer) +{ + switch (buffer) { + case GL_NONE: + return 0; + case GL_FRONT: + return BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_FRONT_RIGHT; + case GL_BACK: + return BUFFER_BIT_BACK_LEFT | BUFFER_BIT_BACK_RIGHT; + case GL_RIGHT: + return BUFFER_BIT_FRONT_RIGHT | BUFFER_BIT_BACK_RIGHT; + case GL_FRONT_RIGHT: + return BUFFER_BIT_FRONT_RIGHT; + case GL_BACK_RIGHT: + return BUFFER_BIT_BACK_RIGHT; + case GL_BACK_LEFT: + return BUFFER_BIT_BACK_LEFT; + case GL_FRONT_AND_BACK: + return BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_BACK_LEFT + | BUFFER_BIT_FRONT_RIGHT | BUFFER_BIT_BACK_RIGHT; + case GL_LEFT: + return BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_BACK_LEFT; + case GL_FRONT_LEFT: + return BUFFER_BIT_FRONT_LEFT; + case GL_AUX0: + return BUFFER_BIT_AUX0; + case GL_AUX1: + case GL_AUX2: + case GL_AUX3: + return 1 << BUFFER_COUNT; /* invalid, but not BAD_MASK */ + case GL_COLOR_ATTACHMENT0_EXT: + return BUFFER_BIT_COLOR0; + case GL_COLOR_ATTACHMENT1_EXT: + return BUFFER_BIT_COLOR1; + case GL_COLOR_ATTACHMENT2_EXT: + return BUFFER_BIT_COLOR2; + case GL_COLOR_ATTACHMENT3_EXT: + return BUFFER_BIT_COLOR3; + case GL_COLOR_ATTACHMENT4_EXT: + return BUFFER_BIT_COLOR4; + case GL_COLOR_ATTACHMENT5_EXT: + return BUFFER_BIT_COLOR5; + case GL_COLOR_ATTACHMENT6_EXT: + return BUFFER_BIT_COLOR6; + case GL_COLOR_ATTACHMENT7_EXT: + return BUFFER_BIT_COLOR7; + default: + /* error */ + return BAD_MASK; + } +} + + +/** + * Helper routine used by glReadBuffer. + * Given a GLenum naming a color buffer, return the index of the corresponding + * renderbuffer (a BUFFER_* value). + * return -1 for an invalid buffer. + */ +static GLint +read_buffer_enum_to_index(GLenum buffer) +{ + switch (buffer) { + case GL_FRONT: + return BUFFER_FRONT_LEFT; + case GL_BACK: + return BUFFER_BACK_LEFT; + case GL_RIGHT: + return BUFFER_FRONT_RIGHT; + case GL_FRONT_RIGHT: + return BUFFER_FRONT_RIGHT; + case GL_BACK_RIGHT: + return BUFFER_BACK_RIGHT; + case GL_BACK_LEFT: + return BUFFER_BACK_LEFT; + case GL_LEFT: + return BUFFER_FRONT_LEFT; + case GL_FRONT_LEFT: + return BUFFER_FRONT_LEFT; + case GL_AUX0: + return BUFFER_AUX0; + case GL_AUX1: + case GL_AUX2: + case GL_AUX3: + return BUFFER_COUNT; /* invalid, but not -1 */ + case GL_COLOR_ATTACHMENT0_EXT: + return BUFFER_COLOR0; + case GL_COLOR_ATTACHMENT1_EXT: + return BUFFER_COLOR1; + case GL_COLOR_ATTACHMENT2_EXT: + return BUFFER_COLOR2; + case GL_COLOR_ATTACHMENT3_EXT: + return BUFFER_COLOR3; + case GL_COLOR_ATTACHMENT4_EXT: + return BUFFER_COLOR4; + case GL_COLOR_ATTACHMENT5_EXT: + return BUFFER_COLOR5; + case GL_COLOR_ATTACHMENT6_EXT: + return BUFFER_COLOR6; + case GL_COLOR_ATTACHMENT7_EXT: + return BUFFER_COLOR7; + default: + /* error */ + return -1; + } +} + + +/** + * Called by glDrawBuffer(). + * Specify which renderbuffer(s) to draw into for the first color output. + * <buffer> can name zero, one, two or four renderbuffers! + * \sa _mesa_DrawBuffersARB + * + * \param buffer buffer token such as GL_LEFT or GL_FRONT_AND_BACK, etc. + * + * Note that the behaviour of this function depends on whether the + * current ctx->DrawBuffer is a window-system framebuffer (Name=0) or + * a user-created framebuffer object (Name!=0). + * In the former case, we update the per-context ctx->Color.DrawBuffer + * state var _and_ the FB's ColorDrawBuffer state. + * In the later case, we update the FB's ColorDrawBuffer state only. + * + * Furthermore, upon a MakeCurrent() or BindFramebuffer() call, if the + * new FB is a window system FB, we need to re-update the FB's + * ColorDrawBuffer state to match the context. This is handled in + * _mesa_update_framebuffer(). + * + * See the GL_EXT_framebuffer_object spec for more info. + */ +void GLAPIENTRY +_mesa_DrawBuffer(GLenum buffer) +{ + GLbitfield destMask; + GET_CURRENT_CONTEXT(ctx); + ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx); /* too complex... */ + + if (MESA_VERBOSE & VERBOSE_API) { + _mesa_debug(ctx, "glDrawBuffer %s\n", _mesa_lookup_enum_by_nr(buffer)); + } + + if (buffer == GL_NONE) { + destMask = 0x0; + } + else { + const GLbitfield supportedMask + = supported_buffer_bitmask(ctx, ctx->DrawBuffer); + destMask = draw_buffer_enum_to_bitmask(buffer); + if (destMask == BAD_MASK) { + /* totally bogus buffer */ + _mesa_error(ctx, GL_INVALID_ENUM, "glDrawBuffer(buffer=0x%x)", buffer); + return; + } + destMask &= supportedMask; + if (destMask == 0x0) { + /* none of the named color buffers exist! */ + _mesa_error(ctx, GL_INVALID_OPERATION, + "glDrawBuffer(buffer=0x%x)", buffer); + return; + } + } + + /* if we get here, there's no error so set new state */ + _mesa_drawbuffers(ctx, 1, &buffer, &destMask); + + /* + * Call device driver function. + */ + if (ctx->Driver.DrawBuffers) + ctx->Driver.DrawBuffers(ctx, 1, &buffer); + else if (ctx->Driver.DrawBuffer) + ctx->Driver.DrawBuffer(ctx, buffer); +} + + +/** + * Called by glDrawBuffersARB; specifies the destination color renderbuffers + * for N fragment program color outputs. + * \sa _mesa_DrawBuffer + * \param n number of outputs + * \param buffers array [n] of renderbuffer names. Unlike glDrawBuffer, the + * names cannot specify more than one buffer. For example, + * GL_FRONT_AND_BACK is illegal. + */ +void GLAPIENTRY +_mesa_DrawBuffersARB(GLsizei n, const GLenum *buffers) +{ + GLint output; + GLbitfield usedBufferMask, supportedMask; + GLbitfield destMask[MAX_DRAW_BUFFERS]; + GET_CURRENT_CONTEXT(ctx); + ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx); + + /* Turns out n==0 is a valid input that should not produce an error. + * The remaining code below correctly handles the n==0 case. + */ + if (n < 0 || n > (GLsizei) ctx->Const.MaxDrawBuffers) { + _mesa_error(ctx, GL_INVALID_VALUE, "glDrawBuffersARB(n)"); + return; + } + + supportedMask = supported_buffer_bitmask(ctx, ctx->DrawBuffer); + usedBufferMask = 0x0; + + /* complicated error checking... */ + for (output = 0; output < n; output++) { + if (buffers[output] == GL_NONE) { + destMask[output] = 0x0; + } + else { + destMask[output] = draw_buffer_enum_to_bitmask(buffers[output]); + if (destMask[output] == BAD_MASK + || _mesa_bitcount(destMask[output]) > 1) { + _mesa_error(ctx, GL_INVALID_ENUM, "glDrawBuffersARB(buffer)"); + return; + } + destMask[output] &= supportedMask; + if (destMask[output] == 0) { + _mesa_error(ctx, GL_INVALID_OPERATION, + "glDrawBuffersARB(unsupported buffer)"); + return; + } + if (destMask[output] & usedBufferMask) { + /* can't specify a dest buffer more than once! */ + _mesa_error(ctx, GL_INVALID_OPERATION, + "glDrawBuffersARB(duplicated buffer)"); + return; + } + + /* update bitmask */ + usedBufferMask |= destMask[output]; + } + } + + /* OK, if we get here, there were no errors so set the new state */ + _mesa_drawbuffers(ctx, n, buffers, destMask); + + /* + * Call device driver function. Note that n can be equal to 0, + * in which case we don't want to reference buffers[0], which + * may not be valid. + */ + if (ctx->Driver.DrawBuffers) + ctx->Driver.DrawBuffers(ctx, n, buffers); + else if (ctx->Driver.DrawBuffer) + ctx->Driver.DrawBuffer(ctx, n > 0 ? buffers[0] : GL_NONE); +} + +/** + * Performs necessary state updates when _mesa_drawbuffers makes an + * actual change. + */ +static void +updated_drawbuffers(struct gl_context *ctx) +{ + FLUSH_VERTICES(ctx, _NEW_BUFFERS); + +#if FEATURE_GL + if (ctx->API == API_OPENGL && !ctx->Extensions.ARB_ES2_compatibility) { + struct gl_framebuffer *fb = ctx->DrawBuffer; + + /* Flag the FBO as requiring validation. */ + if (fb->Name != 0) { + fb->_Status = 0; + } + } +#endif +} + +/** + * Helper function to set the GL_DRAW_BUFFER state in the context and + * current FBO. Called via glDrawBuffer(), glDrawBuffersARB() + * + * All error checking will have been done prior to calling this function + * so nothing should go wrong at this point. + * + * \param ctx current context + * \param n number of color outputs to set + * \param buffers array[n] of colorbuffer names, like GL_LEFT. + * \param destMask array[n] of BUFFER_BIT_* bitmasks which correspond to the + * colorbuffer names. (i.e. GL_FRONT_AND_BACK => + * BUFFER_BIT_FRONT_LEFT | BUFFER_BIT_BACK_LEFT). + */ +void +_mesa_drawbuffers(struct gl_context *ctx, GLuint n, const GLenum *buffers, + const GLbitfield *destMask) +{ + struct gl_framebuffer *fb = ctx->DrawBuffer; + GLbitfield mask[MAX_DRAW_BUFFERS]; + + if (!destMask) { + /* compute destMask values now */ + const GLbitfield supportedMask = supported_buffer_bitmask(ctx, fb); + GLuint output; + for (output = 0; output < n; output++) { + mask[output] = draw_buffer_enum_to_bitmask(buffers[output]); + ASSERT(mask[output] != BAD_MASK); + mask[output] &= supportedMask; + } + destMask = mask; + } + + /* + * If n==1, destMask[0] may have up to four bits set. + * Otherwise, destMask[x] can only have one bit set. + */ + if (n == 1) { + GLuint count = 0, destMask0 = destMask[0]; + while (destMask0) { + GLint bufIndex = _mesa_ffs(destMask0) - 1; + if (fb->_ColorDrawBufferIndexes[count] != bufIndex) { + updated_drawbuffers(ctx); + fb->_ColorDrawBufferIndexes[count] = bufIndex; + } + count++; + destMask0 &= ~(1 << bufIndex); + } + fb->ColorDrawBuffer[0] = buffers[0]; + if (fb->_NumColorDrawBuffers != count) { + updated_drawbuffers(ctx); + fb->_NumColorDrawBuffers = count; + } + } + else { + GLuint buf, count = 0; + for (buf = 0; buf < n; buf++ ) { + if (destMask[buf]) { + GLint bufIndex = _mesa_ffs(destMask[buf]) - 1; + /* only one bit should be set in the destMask[buf] field */ + ASSERT(_mesa_bitcount(destMask[buf]) == 1); + if (fb->_ColorDrawBufferIndexes[buf] != bufIndex) { + updated_drawbuffers(ctx); + fb->_ColorDrawBufferIndexes[buf] = bufIndex; + } + count = buf + 1; + } + else { + if (fb->_ColorDrawBufferIndexes[buf] != -1) { + updated_drawbuffers(ctx); + fb->_ColorDrawBufferIndexes[buf] = -1; + } + } + fb->ColorDrawBuffer[buf] = buffers[buf]; + } + /* set remaining outputs to -1 (GL_NONE) */ + while (buf < ctx->Const.MaxDrawBuffers) { + if (fb->_ColorDrawBufferIndexes[buf] != -1) { + updated_drawbuffers(ctx); + fb->_ColorDrawBufferIndexes[buf] = -1; + } + fb->ColorDrawBuffer[buf] = GL_NONE; + buf++; + } + fb->_NumColorDrawBuffers = count; + } + + if (fb->Name == 0) { + /* also set context drawbuffer state */ + GLuint buf; + for (buf = 0; buf < ctx->Const.MaxDrawBuffers; buf++) { + if (ctx->Color.DrawBuffer[buf] != fb->ColorDrawBuffer[buf]) { + updated_drawbuffers(ctx); + ctx->Color.DrawBuffer[buf] = fb->ColorDrawBuffer[buf]; + } + } + } +} + + +/** + * Like \sa _mesa_drawbuffers(), this is a helper function for setting + * GL_READ_BUFFER state in the context and current FBO. + * \param ctx the rendering context + * \param buffer GL_FRONT, GL_BACK, GL_COLOR_ATTACHMENT0, etc. + * \param bufferIndex the numerical index corresponding to 'buffer' + */ +void +_mesa_readbuffer(struct gl_context *ctx, GLenum buffer, GLint bufferIndex) +{ + struct gl_framebuffer *fb = ctx->ReadBuffer; + + if (fb->Name == 0) { + /* Only update the per-context READ_BUFFER state if we're bound to + * a window-system framebuffer. + */ + ctx->Pixel.ReadBuffer = buffer; + } + + fb->ColorReadBuffer = buffer; + fb->_ColorReadBufferIndex = bufferIndex; + + ctx->NewState |= _NEW_BUFFERS; +} + + + +/** + * Called by glReadBuffer to set the source renderbuffer for reading pixels. + * \param mode color buffer such as GL_FRONT, GL_BACK, etc. + */ +void GLAPIENTRY +_mesa_ReadBuffer(GLenum buffer) +{ + struct gl_framebuffer *fb; + GLbitfield supportedMask; + GLint srcBuffer; + GET_CURRENT_CONTEXT(ctx); + ASSERT_OUTSIDE_BEGIN_END_AND_FLUSH(ctx); + + if (MESA_VERBOSE & VERBOSE_API) + _mesa_debug(ctx, "glReadBuffer %s\n", _mesa_lookup_enum_by_nr(buffer)); + + fb = ctx->ReadBuffer; + + if (MESA_VERBOSE & VERBOSE_API) + _mesa_debug(ctx, "glReadBuffer %s\n", _mesa_lookup_enum_by_nr(buffer)); + + if (fb->Name > 0 && buffer == GL_NONE) { + /* This is legal for user-created framebuffer objects */ + srcBuffer = -1; + } + else { + /* general case / window-system framebuffer */ + srcBuffer = read_buffer_enum_to_index(buffer); + if (srcBuffer == -1) { + _mesa_error(ctx, GL_INVALID_ENUM, + "glReadBuffer(buffer=0x%x)", buffer); + return; + } + supportedMask = supported_buffer_bitmask(ctx, fb); + if (((1 << srcBuffer) & supportedMask) == 0) { + _mesa_error(ctx, GL_INVALID_OPERATION, + "glReadBuffer(buffer=0x%x)", buffer); + return; + } + } + + /* OK, all error checking has been completed now */ + + _mesa_readbuffer(ctx, buffer, srcBuffer); + ctx->NewState |= _NEW_BUFFERS; + + /* + * Call device driver function. + */ + if (ctx->Driver.ReadBuffer) + (*ctx->Driver.ReadBuffer)(ctx, buffer); +} |