summary: Bug 689707. Use lower precision bilinear interpolation. r=joe diff --git a/gfx/cairo/libpixman/src/pixman-bits-image.c b/gfx/cairo/libpixman/src/pixman-bits-image.c --- a/gfx/cairo/libpixman/src/pixman-bits-image.c +++ b/gfx/cairo/libpixman/src/pixman-bits-image.c @@ -124,18 +124,18 @@ bits_image_fetch_pixel_bilinear (bits_im int height = image->height; int x1, y1, x2, y2; uint32_t tl, tr, bl, br; int32_t distx, disty; x1 = x - pixman_fixed_1 / 2; y1 = y - pixman_fixed_1 / 2; - distx = (x1 >> 8) & 0xff; - disty = (y1 >> 8) & 0xff; + distx = interpolation_coord(x1); + disty = interpolation_coord(y1); x1 = pixman_fixed_to_int (x1); y1 = pixman_fixed_to_int (y1); x2 = x1 + 1; y2 = y1 + 1; if (repeat_mode != PIXMAN_REPEAT_NONE) { @@ -190,17 +190,17 @@ bits_image_fetch_bilinear_no_repeat_8888 if (!pixman_transform_point_3d (bits->common.transform, &v)) return; ux = ux_top = ux_bottom = bits->common.transform->matrix[0][0]; x = x_top = x_bottom = v.vector[0] - pixman_fixed_1/2; y = v.vector[1] - pixman_fixed_1/2; - disty = (y >> 8) & 0xff; + disty = interpolation_coord(y); /* Load the pointers to the first and second lines from the source * image that bilinear code must read. * * The main trick in this code is about the check if any line are * outside of the image; * * When I realize that a line (any one) is outside, I change @@ -299,17 +299,17 @@ bits_image_fetch_bilinear_no_repeat_8888 while (buffer < end && x < 0) { uint32_t tr, br; int32_t distx; tr = top_row[pixman_fixed_to_int (x_top) + 1] | top_mask; br = bottom_row[pixman_fixed_to_int (x_bottom) + 1] | bottom_mask; - distx = (x >> 8) & 0xff; + distx = interpolation_coord(x); *buffer++ = bilinear_interpolation (0, tr, 0, br, distx, disty); x += ux; x_top += ux_top; x_bottom += ux_bottom; mask += mask_inc; } @@ -324,17 +324,17 @@ bits_image_fetch_bilinear_no_repeat_8888 uint32_t tl, tr, bl, br; int32_t distx; tl = top_row [pixman_fixed_to_int (x_top)] | top_mask; tr = top_row [pixman_fixed_to_int (x_top) + 1] | top_mask; bl = bottom_row [pixman_fixed_to_int (x_bottom)] | bottom_mask; br = bottom_row [pixman_fixed_to_int (x_bottom) + 1] | bottom_mask; - distx = (x >> 8) & 0xff; + distx = interpolation_coord(x); *buffer = bilinear_interpolation (tl, tr, bl, br, distx, disty); } buffer++; x += ux; x_top += ux_top; x_bottom += ux_bottom; @@ -348,17 +348,17 @@ bits_image_fetch_bilinear_no_repeat_8888 if (*mask) { uint32_t tl, bl; int32_t distx; tl = top_row [pixman_fixed_to_int (x_top)] | top_mask; bl = bottom_row [pixman_fixed_to_int (x_bottom)] | bottom_mask; - distx = (x >> 8) & 0xff; + distx = interpolation_coord(x); *buffer = bilinear_interpolation (tl, 0, bl, 0, distx, disty); } buffer++; x += ux; x_top += ux_top; x_bottom += ux_bottom; @@ -675,18 +675,18 @@ bits_image_fetch_bilinear_affine (pixman const uint8_t *row2; if (mask && !mask[i]) goto next; x1 = x - pixman_fixed_1 / 2; y1 = y - pixman_fixed_1 / 2; - distx = (x1 >> 8) & 0xff; - disty = (y1 >> 8) & 0xff; + distx = interpolation_coord(x1); + disty = interpolation_coord(y1); y1 = pixman_fixed_to_int (y1); y2 = y1 + 1; x1 = pixman_fixed_to_int (x1); x2 = x1 + 1; if (repeat_mode != PIXMAN_REPEAT_NONE) { diff --git a/gfx/cairo/libpixman/src/pixman-inlines.h b/gfx/cairo/libpixman/src/pixman-inlines.h --- a/gfx/cairo/libpixman/src/pixman-inlines.h +++ b/gfx/cairo/libpixman/src/pixman-inlines.h @@ -76,16 +76,31 @@ repeat (pixman_repeat_t repeat, int *c, { *c = MOD (*c, size * 2); if (*c >= size) *c = size * 2 - *c - 1; } return TRUE; } +#ifdef MOZ_GFX_OPTIMIZE_MOBILE +#define LOW_QUALITY_INTERPOLATION +#endif + +static force_inline int32_t +interpolation_coord(pixman_fixed_t t) +{ +#ifdef LOW_QUALITY_INTERPOLATION + return (t >> 12) & 0xf; +#else + return (t >> 8) & 0xff; +#endif +} + + #if SIZEOF_LONG > 4 static force_inline uint32_t bilinear_interpolation (uint32_t tl, uint32_t tr, uint32_t bl, uint32_t br, int distx, int disty) { uint64_t distxy, distxiy, distixy, distixiy; @@ -122,16 +137,44 @@ bilinear_interpolation (uint32_t tl, uin f = tl64 * distixiy + tr64 * distxiy + bl64 * distixy + br64 * distxy; r |= ((f >> 16) & 0x000000ff00000000ull) | (f & 0xff000000ull); return (uint32_t)(r >> 16); } #else +#ifdef LOW_QUALITY_INTERPOLATION +/* Based on Filter_32_opaque_portable from Skia */ +static force_inline uint32_t +bilinear_interpolation(uint32_t a00, uint32_t a01, + uint32_t a10, uint32_t a11, + int x, int y) +{ + int xy = x * y; + static const uint32_t mask = 0xff00ff; + + int scale = 256 - 16*y - 16*x + xy; + uint32_t lo = (a00 & mask) * scale; + uint32_t hi = ((a00 >> 8) & mask) * scale; + + scale = 16*x - xy; + lo += (a01 & mask) * scale; + hi += ((a01 >> 8) & mask) * scale; + + scale = 16*y - xy; + lo += (a10 & mask) * scale; + hi += ((a10 >> 8) & mask) * scale; + + lo += (a11 & mask) * xy; + hi += ((a11 >> 8) & mask) * xy; + + return ((lo >> 8) & mask) | (hi & ~mask); +} +#else static force_inline uint32_t bilinear_interpolation (uint32_t tl, uint32_t tr, uint32_t bl, uint32_t br, int distx, int disty) { int distxy, distxiy, distixy, distixiy; uint32_t f, r; @@ -164,17 +207,17 @@ bilinear_interpolation (uint32_t tl, uin /* Alpha */ f = (tl & 0x0000ff00) * distixiy + (tr & 0x0000ff00) * distxiy + (bl & 0x0000ff00) * distixy + (br & 0x0000ff00) * distxy; r |= f & 0xff000000; return r; } - +#endif #endif /* * For each scanline fetched from source image with PAD repeat: * - calculate how many pixels need to be padded on the left side * - calculate how many pixels need to be padded on the right side * - update width to only count pixels which are fetched from the image * All this information is returned via 'width', 'left_pad', 'right_pad'