The generic C over_u combiner can be a lot faster with the
addition of special shortcuts for 0xFF and 0x00 alpha/mask
values. This is already implemented in C and SSE2 fast paths.
Profiling the run of cairo-perf-trace benchmarks with PIXMAN_DISABLE
environment variable set to "fast mmx sse2" on Intel Core i7:
=== before ===
37.32% cairo-perf-trac libpixman-1.so.0.29.1 [.] combine_over_u
21.37% cairo-perf-trac libpixman-1.so.0.29.1 [.]
bits_image_fetch_bilinear_no_repeat_8888
13.51% cairo-perf-trac libpixman-1.so.0.29.1 [.]
bits_image_fetch_bilinear_affine_none_a8r8g8b8
2.96% cairo-perf-trac libpixman-1.so.0.29.1 [.] radial_compute_color
2.74% cairo-perf-trac libpixman-1.so.0.29.1 [.] fetch_scanline_a8
2.71% cairo-perf-trac libpixman-1.so.0.29.1 [.] fetch_scanline_x8r8g8b8
2.17% cairo-perf-trac libpixman-1.so.0.29.1 [.] _pixman_gradient_walker_pixel
1.86% cairo-perf-trac libcairo.so.2.11200.0 [.]
_cairo_tor_scan_converter_generate
1.57% cairo-perf-trac libpixman-1.so.0.29.1 [.]
bits_image_fetch_bilinear_affine_pad_a8r8g8b8
0.97% cairo-perf-trac libpixman-1.so.0.29.1 [.] combine_in_reverse_u
0.96% cairo-perf-trac libpixman-1.so.0.29.1 [.] combine_over_ca
=== after ===
28.79% cairo-perf-trac libpixman-1.so.0.29.1 [.]
bits_image_fetch_bilinear_no_repeat_8888
18.44% cairo-perf-trac libpixman-1.so.0.29.1 [.]
bits_image_fetch_bilinear_affine_none_a8r8g8b8
15.54% cairo-perf-trac libpixman-1.so.0.29.1 [.] combine_over_u
3.94% cairo-perf-trac libpixman-1.so.0.29.1 [.] radial_compute_color
3.69% cairo-perf-trac libpixman-1.so.0.29.1 [.] fetch_scanline_a8
3.69% cairo-perf-trac libpixman-1.so.0.29.1 [.] fetch_scanline_x8r8g8b8
2.94% cairo-perf-trac libpixman-1.so.0.29.1 [.] _pixman_gradient_walker_pixel
2.52% cairo-perf-trac libcairo.so.2.11200.0 [.]
_cairo_tor_scan_converter_generate
2.08% cairo-perf-trac libpixman-1.so.0.29.1 [.]
bits_image_fetch_bilinear_affine_pad_a8r8g8b8
1.31% cairo-perf-trac libpixman-1.so.0.29.1 [.] combine_in_reverse_u
1.29% cairo-perf-trac libpixman-1.so.0.29.1 [.] combine_over_ca
---
pixman/pixman-combine32.c | 58 +++++++++++++++++++++++++++++++++++++++-----
1 files changed, 51 insertions(+), 7 deletions(-)
diff --git a/pixman/pixman-combine32.c b/pixman/pixman-combine32.c
index 54cc877..3ac7576 100644
--- a/pixman/pixman-combine32.c
+++ b/pixman/pixman-combine32.c
@@ -196,14 +196,58 @@ combine_over_u (pixman_implementation_t *imp,
{
int i;
- for (i = 0; i < width; ++i)
+ if (!mask)
{
- uint32_t s = combine_mask (src, mask, i);
- uint32_t d = *(dest + i);
- uint32_t ia = ALPHA_8 (~s);
-
- UN8x4_MUL_UN8_ADD_UN8x4 (d, ia, s);
- *(dest + i) = d;
+ for (i = 0; i < width; ++i)
+ {
+ uint32_t s = *(src + i);
+ uint32_t a = ALPHA_8 (s);
+ if (a == 0xFF)
+ {
+ *(dest + i) = s;
+ }
+ else if (s)
+ {
+ uint32_t d = *(dest + i);
+ uint32_t ia = a ^ 0xFF;
+ UN8x4_MUL_UN8_ADD_UN8x4 (d, ia, s);
+ *(dest + i) = d;
+ }
+ }
+ }
+ else
+ {
+ for (i = 0; i < width; ++i)
+ {
+ uint32_t m = ALPHA_8 (*(mask + i));
+ if (m == 0xFF)
+ {
+ uint32_t s = *(src + i);
+ uint32_t a = ALPHA_8 (s);
+ if (a == 0xFF)
+ {
+ *(dest + i) = s;
+ }
+ else if (s)
+ {
+ uint32_t d = *(dest + i);
+ uint32_t ia = a ^ 0xFF;
+ UN8x4_MUL_UN8_ADD_UN8x4 (d, ia, s);
+ *(dest + i) = d;
+ }
+ }
+ else if (m)
+ {
+ uint32_t s = *(src + i);
+ if (s)
+ {
+ uint32_t d = *(dest + i);
+ UN8x4_MUL_UN8 (s, m);
+ UN8x4_MUL_UN8_ADD_UN8x4 (d, ALPHA_8 (~s), s);
+ *(dest + i) = d;
+ }
+ }
+ }
}
}
--
1.7.8.6
_______________________________________________
Pixman mailing list
Pixman@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/pixman
