diff options
Diffstat (limited to 'xorg-server/fb/fbtrap.c')
| -rw-r--r-- | xorg-server/fb/fbtrap.c | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/xorg-server/fb/fbtrap.c b/xorg-server/fb/fbtrap.c new file mode 100644 index 000000000..830603ae7 --- /dev/null +++ b/xorg-server/fb/fbtrap.c @@ -0,0 +1,161 @@ +/* + * Copyright © 2004 Keith Packard + * + * Permission to use, copy, modify, distribute, and sell this software and its + * documentation for any purpose is hereby granted without fee, provided that + * the above copyright notice appear in all copies and that both that + * copyright notice and this permission notice appear in supporting + * documentation, and that the name of Keith Packard not be used in + * advertising or publicity pertaining to distribution of the software without + * specific, written prior permission. Keith Packard makes no + * representations about the suitability of this software for any purpose. It + * is provided "as is" without express or implied warranty. + * + * KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, + * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO + * EVENT SHALL KEITH PACKARD BE LIABLE FOR ANY SPECIAL, INDIRECT OR + * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, + * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER + * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR + * PERFORMANCE OF THIS SOFTWARE. + */ + +#ifdef HAVE_DIX_CONFIG_H +#include <dix-config.h> +#endif + +#include "fb.h" + +#ifdef RENDER + +#include "picturestr.h" +#include "mipict.h" +#include "renderedge.h" +#include "fbpict.h" + +void +fbAddTraps (PicturePtr pPicture, + INT16 x_off, + INT16 y_off, + int ntrap, + xTrap *traps) +{ + pixman_image_t *image = image_from_pict (pPicture, FALSE); + + if (!image) + return; + + pixman_add_traps (image, x_off, y_off, ntrap, (pixman_trap_t *)traps); + + free_pixman_pict (pPicture, image); +} + +void +fbRasterizeTrapezoid (PicturePtr pPicture, + xTrapezoid *trap, + int x_off, + int y_off) +{ + pixman_image_t *image = image_from_pict (pPicture, FALSE); + + if (!image) + return; + + pixman_rasterize_trapezoid (image, (pixman_trapezoid_t *)trap, x_off, y_off); + + free_pixman_pict (pPicture, image); +} + +static int +_GreaterY (xPointFixed *a, xPointFixed *b) +{ + if (a->y == b->y) + return a->x > b->x; + return a->y > b->y; +} + +/* + * Note that the definition of this function is a bit odd because + * of the X coordinate space (y increasing downwards). + */ +static int +_Clockwise (xPointFixed *ref, xPointFixed *a, xPointFixed *b) +{ + xPointFixed ad, bd; + + ad.x = a->x - ref->x; + ad.y = a->y - ref->y; + bd.x = b->x - ref->x; + bd.y = b->y - ref->y; + + return ((xFixed_32_32) bd.y * ad.x - (xFixed_32_32) ad.y * bd.x) < 0; +} + +/* FIXME -- this could be made more efficient */ +void +fbAddTriangles (PicturePtr pPicture, + INT16 x_off, + INT16 y_off, + int ntri, + xTriangle *tris) +{ + xPointFixed *top, *left, *right, *tmp; + xTrapezoid trap; + + for (; ntri; ntri--, tris++) + { + top = &tris->p1; + left = &tris->p2; + right = &tris->p3; + if (_GreaterY (top, left)) { + tmp = left; left = top; top = tmp; + } + if (_GreaterY (top, right)) { + tmp = right; right = top; top = tmp; + } + if (_Clockwise (top, right, left)) { + tmp = right; right = left; left = tmp; + } + + /* + * Two cases: + * + * + + + * / \ / \ + * / \ / \ + * / + + \ + * / -- -- \ + * / -- -- \ + * / --- --- \ + * +-- --+ + */ + + trap.top = top->y; + trap.left.p1 = *top; + trap.left.p2 = *left; + trap.right.p1 = *top; + trap.right.p2 = *right; + if (right->y < left->y) + trap.bottom = right->y; + else + trap.bottom = left->y; + fbRasterizeTrapezoid (pPicture, &trap, x_off, y_off); + if (right->y < left->y) + { + trap.top = right->y; + trap.bottom = left->y; + trap.right.p1 = *right; + trap.right.p2 = *left; + } + else + { + trap.top = left->y; + trap.bottom = right->y; + trap.left.p1 = *left; + trap.left.p2 = *right; + } + fbRasterizeTrapezoid (pPicture, &trap, x_off, y_off); + } +} + +#endif /* RENDER */ |