weston/tests/color_util.c
Vitaly Prosyak 15d7546b2d tests: refactoring alpha-blending
No functional change. Moved color processing
functions into shared files which can be used
between different tests.

Signed-off-by: Vitaly Prosyak <vitaly.prosyak@amd.com>
2021-11-13 00:17:03 +00:00

85 lines
2.1 KiB
C

/*
* Copyright 2020 Collabora, Ltd.
* Copyright 2021 Advanced Micro Devices, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial
* portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include "config.h"
#include <math.h>
#include "color_util.h"
#include <assert.h>
static float
sRGB_EOTF(float e)
{
assert(e >= 0.0f);
assert(e <= 1.0f);
if (e <= 0.04045)
return e / 12.92;
else
return pow((e + 0.055) / 1.055, 2.4);
}
static float
sRGB_EOTF_inv(float o)
{
assert(o >= 0.0f);
assert(o <= 1.0f);
if (o <= 0.04045 / 12.92)
return o * 12.92;
else
return pow(o, 1.0 / 2.4) * 1.055 - 0.055;
}
void
sRGB_linearize(struct color_float *cf)
{
cf->r = sRGB_EOTF(cf->r);
cf->g = sRGB_EOTF(cf->g);
cf->b = sRGB_EOTF(cf->b);
}
void
sRGB_delinearize(struct color_float *cf)
{
cf->r = sRGB_EOTF_inv(cf->r);
cf->g = sRGB_EOTF_inv(cf->g);
cf->b = sRGB_EOTF_inv(cf->b);
}
struct color_float
a8r8g8b8_to_float(uint32_t v)
{
struct color_float cf;
cf.a = ((v >> 24) & 0xff) / 255.f;
cf.r = ((v >> 16) & 0xff) / 255.f;
cf.g = ((v >> 8) & 0xff) / 255.f;
cf.b = ((v >> 0) & 0xff) / 255.f;
return cf;
}