--- /dev/null
+/*
+ * 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.
+ */
+
+#ifndef rasterize_span
+#endif
+
+static void
+RASTERIZE_EDGES (pixman_image_t *image,
+ pixman_edge_t *l,
+ pixman_edge_t *r,
+ pixman_fixed_t t,
+ pixman_fixed_t b)
+{
+ pixman_fixed_t y = t;
+ uint32_t *line;
+ uint32_t *buf = (image)->bits.bits;
+ int stride = (image)->bits.rowstride;
+ int width = (image)->bits.width;
+
+ line = buf + pixman_fixed_to_int (y) * stride;
+
+ for (;;)
+ {
+ pixman_fixed_t lx;
+ pixman_fixed_t rx;
+ int lxi;
+ int rxi;
+
+ lx = l->x;
+ rx = r->x;
+#if N_BITS == 1
+ /* For the non-antialiased case, round the coordinates up, in effect
+ * sampling just slightly to the left of the pixel. This is so that
+ * when the sample point lies exactly on the line, we round towards
+ * north-west.
+ *
+ * (The AA case does a similar adjustment in RENDER_SAMPLES_X)
+ */
+ lx += X_FRAC_FIRST(1) - pixman_fixed_e;
+ rx += X_FRAC_FIRST(1) - pixman_fixed_e;
+#endif
+ /* clip X */
+ if (lx < 0)
+ lx = 0;
+ if (pixman_fixed_to_int (rx) >= width)
+#if N_BITS == 1
+ rx = pixman_int_to_fixed (width);
+#else
+ /* Use the last pixel of the scanline, covered 100%.
+ * We can't use the first pixel following the scanline,
+ * because accessing it could result in a buffer overrun.
+ */
+ rx = pixman_int_to_fixed (width) - 1;
+#endif
+
+ /* Skip empty (or backwards) sections */
+ if (rx > lx)
+ {
+
+ /* Find pixel bounds for span */
+ lxi = pixman_fixed_to_int (lx);
+ rxi = pixman_fixed_to_int (rx);
+
+#if N_BITS == 1
+ {
+
+#define LEFT_MASK(x) \
+ (((x) & 0x1f) ? \
+ SCREEN_SHIFT_RIGHT (0xffffffff, (x) & 0x1f) : 0)
+#define RIGHT_MASK(x) \
+ (((32 - (x)) & 0x1f) ? \
+ SCREEN_SHIFT_LEFT (0xffffffff, (32 - (x)) & 0x1f) : 0)
+
+#define MASK_BITS(x,w,l,n,r) { \
+ n = (w); \
+ r = RIGHT_MASK ((x) + n); \
+ l = LEFT_MASK (x); \
+ if (l) { \
+ n -= 32 - ((x) & 0x1f); \
+ if (n < 0) { \
+ n = 0; \
+ l &= r; \
+ r = 0; \
+ } \
+ } \
+ n >>= 5; \
+ }
+
+ uint32_t *a = line;
+ uint32_t startmask;
+ uint32_t endmask;
+ int nmiddle;
+ int width = rxi - lxi;
+ int x = lxi;
+
+ a += x >> 5;
+ x &= 0x1f;
+
+ MASK_BITS (x, width, startmask, nmiddle, endmask);
+
+ if (startmask) {
+ WRITE(image, a, READ(image, a) | startmask);
+ a++;
+ }
+ while (nmiddle--)
+ WRITE(image, a++, 0xffffffff);
+ if (endmask)
+ WRITE(image, a, READ(image, a) | endmask);
+ }
+#else
+ {
+ DEFINE_ALPHA(line,lxi);
+ int lxs;
+ int rxs;
+
+ /* Sample coverage for edge pixels */
+ lxs = RENDER_SAMPLES_X (lx, N_BITS);
+ rxs = RENDER_SAMPLES_X (rx, N_BITS);
+
+ /* Add coverage across row */
+ if (lxi == rxi)
+ {
+ ADD_ALPHA (rxs - lxs);
+ }
+ else
+ {
+ int xi;
+
+ ADD_ALPHA (N_X_FRAC(N_BITS) - lxs);
+ STEP_ALPHA;
+ for (xi = lxi + 1; xi < rxi; xi++)
+ {
+ ADD_ALPHA (N_X_FRAC(N_BITS));
+ STEP_ALPHA;
+ }
+ ADD_ALPHA (rxs);
+ }
+ }
+#endif
+ }
+
+ if (y == b)
+ break;
+
+#if N_BITS > 1
+ if (pixman_fixed_frac (y) != Y_FRAC_LAST(N_BITS))
+ {
+ RENDER_EDGE_STEP_SMALL (l);
+ RENDER_EDGE_STEP_SMALL (r);
+ y += STEP_Y_SMALL(N_BITS);
+ }
+ else
+#endif
+ {
+ RENDER_EDGE_STEP_BIG (l);
+ RENDER_EDGE_STEP_BIG (r);
+ y += STEP_Y_BIG(N_BITS);
+ line += stride;
+ }
+ }
+}
+
+#undef rasterize_span
Code Review / kvmfornfv.git / blobdiff