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Diffstat (limited to '')
| -rw-r--r-- | gfx/cairo/libpixman/src/pixman-edge.c | 385 |
1 files changed, 385 insertions, 0 deletions
diff --git a/gfx/cairo/libpixman/src/pixman-edge.c b/gfx/cairo/libpixman/src/pixman-edge.c new file mode 100644 index 0000000000..ad6dfc4cfa --- /dev/null +++ b/gfx/cairo/libpixman/src/pixman-edge.c @@ -0,0 +1,385 @@ +/* + * 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_CONFIG_H +#include <config.h> +#endif + +#include <string.h> + +#include "pixman-private.h" +#include "pixman-accessor.h" + +/* + * Step across a small sample grid gap + */ +#define RENDER_EDGE_STEP_SMALL(edge) \ + { \ + edge->x += edge->stepx_small; \ + edge->e += edge->dx_small; \ + if (edge->e > 0) \ + { \ + edge->e -= edge->dy; \ + edge->x += edge->signdx; \ + } \ + } + +/* + * Step across a large sample grid gap + */ +#define RENDER_EDGE_STEP_BIG(edge) \ + { \ + edge->x += edge->stepx_big; \ + edge->e += edge->dx_big; \ + if (edge->e > 0) \ + { \ + edge->e -= edge->dy; \ + edge->x += edge->signdx; \ + } \ + } + +#ifdef PIXMAN_FB_ACCESSORS +#define PIXMAN_RASTERIZE_EDGES pixman_rasterize_edges_accessors +#else +#define PIXMAN_RASTERIZE_EDGES pixman_rasterize_edges_no_accessors +#endif + +/* + * 4 bit alpha + */ + +#define N_BITS 4 +#define RASTERIZE_EDGES rasterize_edges_4 + +#ifndef WORDS_BIGENDIAN +#define SHIFT_4(o) ((o) << 2) +#else +#define SHIFT_4(o) ((1 - (o)) << 2) +#endif + +#define GET_4(x, o) (((x) >> SHIFT_4 (o)) & 0xf) +#define PUT_4(x, o, v) \ + (((x) & ~(0xf << SHIFT_4 (o))) | (((v) & 0xf) << SHIFT_4 (o))) + +#define DEFINE_ALPHA(line, x) \ + uint8_t *__ap = (uint8_t *) line + ((x) >> 1); \ + int __ao = (x) & 1 + +#define STEP_ALPHA ((__ap += __ao), (__ao ^= 1)) + +#define ADD_ALPHA(a) \ + { \ + uint8_t __o = READ (image, __ap); \ + uint8_t __a = (a) + GET_4 (__o, __ao); \ + WRITE (image, __ap, PUT_4 (__o, __ao, __a | (0 - ((__a) >> 4)))); \ + } + +#include "pixman-edge-imp.h" + +#undef ADD_ALPHA +#undef STEP_ALPHA +#undef DEFINE_ALPHA +#undef RASTERIZE_EDGES +#undef N_BITS + + +/* + * 1 bit alpha + */ + +#define N_BITS 1 +#define RASTERIZE_EDGES rasterize_edges_1 + +#include "pixman-edge-imp.h" + +#undef RASTERIZE_EDGES +#undef N_BITS + +/* + * 8 bit alpha + */ + +static force_inline uint8_t +clip255 (int x) +{ + if (x > 255) + return 255; + + return x; +} + +#define ADD_SATURATE_8(buf, val, length) \ + do \ + { \ + int i__ = (length); \ + uint8_t *buf__ = (buf); \ + int val__ = (val); \ + \ + while (i__--) \ + { \ + WRITE (image, (buf__), clip255 (READ (image, (buf__)) + (val__))); \ + (buf__)++; \ + } \ + } while (0) + +/* + * We want to detect the case where we add the same value to a long + * span of pixels. The triangles on the end are filled in while we + * count how many sub-pixel scanlines contribute to the middle section. + * + * +--------------------------+ + * fill_height =| \ / + * +------------------+ + * |================| + * fill_start fill_end + */ +static void +rasterize_edges_8 (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; + int fill_start = -1, fill_end = -1; + int fill_size = 0; + 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 (;;) + { + uint8_t *ap = (uint8_t *) line; + pixman_fixed_t lx, rx; + int lxi, rxi; + + /* clip X */ + lx = l->x; + if (lx < 0) + lx = 0; + + rx = r->x; + + if (pixman_fixed_to_int (rx) >= width) + { + /* 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; + } + + /* Skip empty (or backwards) sections */ + if (rx > lx) + { + int lxs, rxs; + + /* Find pixel bounds for span. */ + lxi = pixman_fixed_to_int (lx); + rxi = pixman_fixed_to_int (rx); + + /* Sample coverage for edge pixels */ + lxs = RENDER_SAMPLES_X (lx, 8); + rxs = RENDER_SAMPLES_X (rx, 8); + + /* Add coverage across row */ + if (lxi == rxi) + { + WRITE (image, ap + lxi, + clip255 (READ (image, ap + lxi) + rxs - lxs)); + } + else + { + WRITE (image, ap + lxi, + clip255 (READ (image, ap + lxi) + N_X_FRAC (8) - lxs)); + + /* Move forward so that lxi/rxi is the pixel span */ + lxi++; + + /* Don't bother trying to optimize the fill unless + * the span is longer than 4 pixels. */ + if (rxi - lxi > 4) + { + if (fill_start < 0) + { + fill_start = lxi; + fill_end = rxi; + fill_size++; + } + else + { + if (lxi >= fill_end || rxi < fill_start) + { + /* We're beyond what we saved, just fill it */ + ADD_SATURATE_8 (ap + fill_start, + fill_size * N_X_FRAC (8), + fill_end - fill_start); + fill_start = lxi; + fill_end = rxi; + fill_size = 1; + } + else + { + /* Update fill_start */ + if (lxi > fill_start) + { + ADD_SATURATE_8 (ap + fill_start, + fill_size * N_X_FRAC (8), + lxi - fill_start); + fill_start = lxi; + } + else if (lxi < fill_start) + { + ADD_SATURATE_8 (ap + lxi, N_X_FRAC (8), + fill_start - lxi); + } + + /* Update fill_end */ + if (rxi < fill_end) + { + ADD_SATURATE_8 (ap + rxi, + fill_size * N_X_FRAC (8), + fill_end - rxi); + fill_end = rxi; + } + else if (fill_end < rxi) + { + ADD_SATURATE_8 (ap + fill_end, + N_X_FRAC (8), + rxi - fill_end); + } + fill_size++; + } + } + } + else + { + ADD_SATURATE_8 (ap + lxi, N_X_FRAC (8), rxi - lxi); + } + + WRITE (image, ap + rxi, clip255 (READ (image, ap + rxi) + rxs)); + } + } + + if (y == b) + { + /* We're done, make sure we clean up any remaining fill. */ + if (fill_start != fill_end) + { + if (fill_size == N_Y_FRAC (8)) + { + MEMSET_WRAPPED (image, ap + fill_start, + 0xff, fill_end - fill_start); + } + else + { + ADD_SATURATE_8 (ap + fill_start, fill_size * N_X_FRAC (8), + fill_end - fill_start); + } + } + break; + } + + if (pixman_fixed_frac (y) != Y_FRAC_LAST (8)) + { + RENDER_EDGE_STEP_SMALL (l); + RENDER_EDGE_STEP_SMALL (r); + y += STEP_Y_SMALL (8); + } + else + { + RENDER_EDGE_STEP_BIG (l); + RENDER_EDGE_STEP_BIG (r); + y += STEP_Y_BIG (8); + if (fill_start != fill_end) + { + if (fill_size == N_Y_FRAC (8)) + { + MEMSET_WRAPPED (image, ap + fill_start, + 0xff, fill_end - fill_start); + } + else + { + ADD_SATURATE_8 (ap + fill_start, fill_size * N_X_FRAC (8), + fill_end - fill_start); + } + + fill_start = fill_end = -1; + fill_size = 0; + } + + line += stride; + } + } +} + +#ifndef PIXMAN_FB_ACCESSORS +static +#endif +void +PIXMAN_RASTERIZE_EDGES (pixman_image_t *image, + pixman_edge_t * l, + pixman_edge_t * r, + pixman_fixed_t t, + pixman_fixed_t b) +{ + switch (PIXMAN_FORMAT_BPP (image->bits.format)) + { + case 1: + rasterize_edges_1 (image, l, r, t, b); + break; + + case 4: + rasterize_edges_4 (image, l, r, t, b); + break; + + case 8: + rasterize_edges_8 (image, l, r, t, b); + break; + + default: + break; + } +} + +#ifndef PIXMAN_FB_ACCESSORS + +PIXMAN_EXPORT void +pixman_rasterize_edges (pixman_image_t *image, + pixman_edge_t * l, + pixman_edge_t * r, + pixman_fixed_t t, + pixman_fixed_t b) +{ + return_if_fail (image->type == BITS); + return_if_fail (PIXMAN_FORMAT_TYPE (image->bits.format) == PIXMAN_TYPE_A); + + if (image->bits.read_func || image->bits.write_func) + pixman_rasterize_edges_accessors (image, l, r, t, b); + else + pixman_rasterize_edges_no_accessors (image, l, r, t, b); +} + +#endif |