| /* |
| * 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 |