diff options
Diffstat (limited to 'pixman/pixman/pixman-utils.c')
| -rw-r--r-- | pixman/pixman/pixman-utils.c | 198 |
1 files changed, 114 insertions, 84 deletions
diff --git a/pixman/pixman/pixman-utils.c b/pixman/pixman/pixman-utils.c index 5633f8f79..b1e9fb62d 100644 --- a/pixman/pixman/pixman-utils.c +++ b/pixman/pixman/pixman-utils.c @@ -71,59 +71,96 @@ pixman_malloc_abc (unsigned int a, return malloc (a * b * c); } -static void -unorm_to_unorm_params (int in_width, int out_width, uint32_t *factor, int *shift) +static force_inline uint16_t +float_to_unorm (float f, int n_bits) { - int w = 0; + uint32_t u; - *factor = 0; - while (in_width != 0 && w < out_width) - { - *factor |= 1 << w; - w += in_width; - } + if (f > 1.0) + f = 1.0; + if (f < 0.0) + f = 0.0; + + u = f * (1 << n_bits); + u -= (u >> n_bits); + + return u; +} + +static force_inline float +unorm_to_float (uint16_t u, int n_bits) +{ + uint32_t m = ((1 << n_bits) - 1); - /* Did we generate too many bits? */ - *shift = w - out_width; + return (u & m) * (1.f / (float)m); } /* - * This function expands images from ARGB8 format to ARGB16. To preserve - * precision, it needs to know the original source format. For example, if the - * source was PIXMAN_x1r5g5b5 and the red component contained bits 12345, then - * the expanded value is 12345123. To correctly expand this to 16 bits, it - * should be 1234512345123451 and not 1234512312345123. + * This function expands images from a8r8g8b8 to argb_t. To preserve + * precision, it needs to know from which source format the a8r8g8b8 pixels + * originally came. + * + * For example, if the source was PIXMAN_x1r5g5b5 and the red component + * contained bits 12345, then the 8-bit value is 12345123. To correctly + * expand this to floating point, it should be 12345 / 31.0 and not + * 12345123 / 255.0. */ void -pixman_expand (uint64_t * dst, - const uint32_t * src, - pixman_format_code_t format, - int width) +pixman_expand_to_float (argb_t *dst, + const uint32_t *src, + pixman_format_code_t format, + int width) { + static const float multipliers[16] = { + 0.0f, + 1.0f / ((1 << 1) - 1), + 1.0f / ((1 << 2) - 1), + 1.0f / ((1 << 3) - 1), + 1.0f / ((1 << 4) - 1), + 1.0f / ((1 << 5) - 1), + 1.0f / ((1 << 6) - 1), + 1.0f / ((1 << 7) - 1), + 1.0f / ((1 << 8) - 1), + 1.0f / ((1 << 9) - 1), + 1.0f / ((1 << 10) - 1), + 1.0f / ((1 << 11) - 1), + 1.0f / ((1 << 12) - 1), + 1.0f / ((1 << 13) - 1), + 1.0f / ((1 << 14) - 1), + 1.0f / ((1 << 15) - 1), + }; + int a_size, r_size, g_size, b_size; + int a_shift, r_shift, g_shift, b_shift; + float a_mul, r_mul, g_mul, b_mul; + uint32_t a_mask, r_mask, g_mask, b_mask; + int i; + + if (!PIXMAN_FORMAT_VIS (format)) + format = PIXMAN_a8r8g8b8; + /* * Determine the sizes of each component and the masks and shifts * required to extract them from the source pixel. */ - const int a_size = PIXMAN_FORMAT_A (format), - r_size = PIXMAN_FORMAT_R (format), - g_size = PIXMAN_FORMAT_G (format), - b_size = PIXMAN_FORMAT_B (format); - const int a_shift = 32 - a_size, - r_shift = 24 - r_size, - g_shift = 16 - g_size, - b_shift = 8 - b_size; - const uint8_t a_mask = ~(~0 << a_size), - r_mask = ~(~0 << r_size), - g_mask = ~(~0 << g_size), - b_mask = ~(~0 << b_size); - uint32_t au_factor, ru_factor, gu_factor, bu_factor; - int au_shift, ru_shift, gu_shift, bu_shift; - int i; - - unorm_to_unorm_params (a_size, 16, &au_factor, &au_shift); - unorm_to_unorm_params (r_size, 16, &ru_factor, &ru_shift); - unorm_to_unorm_params (g_size, 16, &gu_factor, &gu_shift); - unorm_to_unorm_params (b_size, 16, &bu_factor, &bu_shift); + a_size = PIXMAN_FORMAT_A (format); + r_size = PIXMAN_FORMAT_R (format); + g_size = PIXMAN_FORMAT_G (format); + b_size = PIXMAN_FORMAT_B (format); + + a_shift = 32 - a_size; + r_shift = 24 - r_size; + g_shift = 16 - g_size; + b_shift = 8 - b_size; + + a_mask = ((1 << a_size) - 1); + r_mask = ((1 << r_size) - 1); + g_mask = ((1 << g_size) - 1); + b_mask = ((1 << b_size) - 1); + + a_mul = multipliers[a_size]; + r_mul = multipliers[r_size]; + g_mul = multipliers[g_size]; + b_mul = multipliers[b_size]; /* Start at the end so that we can do the expansion in place * when src == dst @@ -131,59 +168,43 @@ pixman_expand (uint64_t * dst, for (i = width - 1; i >= 0; i--) { const uint32_t pixel = src[i]; - uint8_t a, r, g, b; - uint64_t a16, r16, g16, b16; - - if (a_size) - { - a = (pixel >> a_shift) & a_mask; - a16 = a * au_factor >> au_shift; - } - else - { - a16 = 0xffff; - } - - if (r_size) - { - r = (pixel >> r_shift) & r_mask; - g = (pixel >> g_shift) & g_mask; - b = (pixel >> b_shift) & b_mask; - r16 = r * ru_factor >> ru_shift; - g16 = g * gu_factor >> gu_shift; - b16 = b * bu_factor >> bu_shift; - } - else - { - r16 = g16 = b16 = 0; - } - - dst[i] = a16 << 48 | r16 << 32 | g16 << 16 | b16; + + dst[i].a = a_mask? ((pixel >> a_shift) & a_mask) * a_mul : 1.0f; + dst[i].r = ((pixel >> r_shift) & r_mask) * r_mul; + dst[i].g = ((pixel >> g_shift) & g_mask) * g_mul; + dst[i].b = ((pixel >> b_shift) & b_mask) * b_mul; } } -/* - * Contracting is easier than expanding. We just need to truncate the - * components. - */ +uint16_t +pixman_float_to_unorm (float f, int n_bits) +{ + return float_to_unorm (f, n_bits); +} + +float +pixman_unorm_to_float (uint16_t u, int n_bits) +{ + return unorm_to_float (u, n_bits); +} + void -pixman_contract (uint32_t * dst, - const uint64_t *src, - int width) +pixman_contract_from_float (uint32_t *dst, + const argb_t *src, + int width) { int i; - /* Start at the beginning so that we can do the contraction in - * place when src == dst - */ - for (i = 0; i < width; i++) + for (i = 0; i < width; ++i) { - const uint8_t a = src[i] >> 56, - r = src[i] >> 40, - g = src[i] >> 24, - b = src[i] >> 8; + uint8_t a, r, g, b; - dst[i] = a << 24 | r << 16 | g << 8 | b; + a = float_to_unorm (src[i].a, 8); + r = float_to_unorm (src[i].r, 8); + g = float_to_unorm (src[i].g, 8); + b = float_to_unorm (src[i].b, 8); + + dst[i] = (a << 24) | (r << 16) | (g << 8) | (b << 0); } } @@ -262,6 +283,15 @@ pixman_region32_copy_from_region16 (pixman_region32_t *dst, return retval; } +/* This function is exported for the sake of the test suite and not part + * of the ABI. + */ +PIXMAN_EXPORT pixman_implementation_t * +_pixman_internal_only_get_implementation (void) +{ + return get_implementation (); +} + #ifdef DEBUG void |