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diff --git a/xorg-server/fb/fbtrap.c b/xorg-server/fb/fbtrap.c
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+/*
+ * 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 */