1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/cairo/libpixman/src/pixman-edge-imp.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,182 @@
1.4 +/*
1.5 + * Copyright © 2004 Keith Packard
1.6 + *
1.7 + * Permission to use, copy, modify, distribute, and sell this software and its
1.8 + * documentation for any purpose is hereby granted without fee, provided that
1.9 + * the above copyright notice appear in all copies and that both that
1.10 + * copyright notice and this permission notice appear in supporting
1.11 + * documentation, and that the name of Keith Packard not be used in
1.12 + * advertising or publicity pertaining to distribution of the software without
1.13 + * specific, written prior permission. Keith Packard makes no
1.14 + * representations about the suitability of this software for any purpose. It
1.15 + * is provided "as is" without express or implied warranty.
1.16 + *
1.17 + * KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
1.18 + * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
1.19 + * EVENT SHALL KEITH PACKARD BE LIABLE FOR ANY SPECIAL, INDIRECT OR
1.20 + * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
1.21 + * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
1.22 + * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
1.23 + * PERFORMANCE OF THIS SOFTWARE.
1.24 + */
1.25 +
1.26 +#ifndef rasterize_span
1.27 +#endif
1.28 +
1.29 +static void
1.30 +RASTERIZE_EDGES (pixman_image_t *image,
1.31 + pixman_edge_t *l,
1.32 + pixman_edge_t *r,
1.33 + pixman_fixed_t t,
1.34 + pixman_fixed_t b)
1.35 +{
1.36 + pixman_fixed_t y = t;
1.37 + uint32_t *line;
1.38 + uint32_t *buf = (image)->bits.bits;
1.39 + int stride = (image)->bits.rowstride;
1.40 + int width = (image)->bits.width;
1.41 +
1.42 + line = buf + pixman_fixed_to_int (y) * stride;
1.43 +
1.44 + for (;;)
1.45 + {
1.46 + pixman_fixed_t lx;
1.47 + pixman_fixed_t rx;
1.48 + int lxi;
1.49 + int rxi;
1.50 +
1.51 + lx = l->x;
1.52 + rx = r->x;
1.53 +#if N_BITS == 1
1.54 + /* For the non-antialiased case, round the coordinates up, in effect
1.55 + * sampling just slightly to the left of the pixel. This is so that
1.56 + * when the sample point lies exactly on the line, we round towards
1.57 + * north-west.
1.58 + *
1.59 + * (The AA case does a similar adjustment in RENDER_SAMPLES_X)
1.60 + */
1.61 + lx += X_FRAC_FIRST(1) - pixman_fixed_e;
1.62 + rx += X_FRAC_FIRST(1) - pixman_fixed_e;
1.63 +#endif
1.64 + /* clip X */
1.65 + if (lx < 0)
1.66 + lx = 0;
1.67 + if (pixman_fixed_to_int (rx) >= width)
1.68 +#if N_BITS == 1
1.69 + rx = pixman_int_to_fixed (width);
1.70 +#else
1.71 + /* Use the last pixel of the scanline, covered 100%.
1.72 + * We can't use the first pixel following the scanline,
1.73 + * because accessing it could result in a buffer overrun.
1.74 + */
1.75 + rx = pixman_int_to_fixed (width) - 1;
1.76 +#endif
1.77 +
1.78 + /* Skip empty (or backwards) sections */
1.79 + if (rx > lx)
1.80 + {
1.81 +
1.82 + /* Find pixel bounds for span */
1.83 + lxi = pixman_fixed_to_int (lx);
1.84 + rxi = pixman_fixed_to_int (rx);
1.85 +
1.86 +#if N_BITS == 1
1.87 + {
1.88 +
1.89 +#define LEFT_MASK(x) \
1.90 + (((x) & 0x1f) ? \
1.91 + SCREEN_SHIFT_RIGHT (0xffffffff, (x) & 0x1f) : 0)
1.92 +#define RIGHT_MASK(x) \
1.93 + (((32 - (x)) & 0x1f) ? \
1.94 + SCREEN_SHIFT_LEFT (0xffffffff, (32 - (x)) & 0x1f) : 0)
1.95 +
1.96 +#define MASK_BITS(x,w,l,n,r) { \
1.97 + n = (w); \
1.98 + r = RIGHT_MASK ((x) + n); \
1.99 + l = LEFT_MASK (x); \
1.100 + if (l) { \
1.101 + n -= 32 - ((x) & 0x1f); \
1.102 + if (n < 0) { \
1.103 + n = 0; \
1.104 + l &= r; \
1.105 + r = 0; \
1.106 + } \
1.107 + } \
1.108 + n >>= 5; \
1.109 + }
1.110 +
1.111 + uint32_t *a = line;
1.112 + uint32_t startmask;
1.113 + uint32_t endmask;
1.114 + int nmiddle;
1.115 + int width = rxi - lxi;
1.116 + int x = lxi;
1.117 +
1.118 + a += x >> 5;
1.119 + x &= 0x1f;
1.120 +
1.121 + MASK_BITS (x, width, startmask, nmiddle, endmask);
1.122 +
1.123 + if (startmask) {
1.124 + WRITE(image, a, READ(image, a) | startmask);
1.125 + a++;
1.126 + }
1.127 + while (nmiddle--)
1.128 + WRITE(image, a++, 0xffffffff);
1.129 + if (endmask)
1.130 + WRITE(image, a, READ(image, a) | endmask);
1.131 + }
1.132 +#else
1.133 + {
1.134 + DEFINE_ALPHA(line,lxi);
1.135 + int lxs;
1.136 + int rxs;
1.137 +
1.138 + /* Sample coverage for edge pixels */
1.139 + lxs = RENDER_SAMPLES_X (lx, N_BITS);
1.140 + rxs = RENDER_SAMPLES_X (rx, N_BITS);
1.141 +
1.142 + /* Add coverage across row */
1.143 + if (lxi == rxi)
1.144 + {
1.145 + ADD_ALPHA (rxs - lxs);
1.146 + }
1.147 + else
1.148 + {
1.149 + int xi;
1.150 +
1.151 + ADD_ALPHA (N_X_FRAC(N_BITS) - lxs);
1.152 + STEP_ALPHA;
1.153 + for (xi = lxi + 1; xi < rxi; xi++)
1.154 + {
1.155 + ADD_ALPHA (N_X_FRAC(N_BITS));
1.156 + STEP_ALPHA;
1.157 + }
1.158 + ADD_ALPHA (rxs);
1.159 + }
1.160 + }
1.161 +#endif
1.162 + }
1.163 +
1.164 + if (y == b)
1.165 + break;
1.166 +
1.167 +#if N_BITS > 1
1.168 + if (pixman_fixed_frac (y) != Y_FRAC_LAST(N_BITS))
1.169 + {
1.170 + RENDER_EDGE_STEP_SMALL (l);
1.171 + RENDER_EDGE_STEP_SMALL (r);
1.172 + y += STEP_Y_SMALL(N_BITS);
1.173 + }
1.174 + else
1.175 +#endif
1.176 + {
1.177 + RENDER_EDGE_STEP_BIG (l);
1.178 + RENDER_EDGE_STEP_BIG (r);
1.179 + y += STEP_Y_BIG(N_BITS);
1.180 + line += stride;
1.181 + }
1.182 + }
1.183 +}
1.184 +
1.185 +#undef rasterize_span
