mirror of
https://github.com/kmc-jp/n64-emu.git
synced 2025-04-02 10:21:43 -04:00
71 lines
2.2 KiB
C
71 lines
2.2 KiB
C
/* Copyright (c) 2020 Themaister
|
|
*
|
|
* 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 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.
|
|
*/
|
|
|
|
#ifndef NOISE_H_
|
|
#define NOISE_H_
|
|
|
|
u16 seeded_noise = U16_C(0);
|
|
|
|
// From: https://www.shadertoy.com/view/XlXcW4 with slight modifications.
|
|
void reseed_noise(uint x, uint y, uint primitive_offset)
|
|
{
|
|
const uint NOISE_PRIME = 1103515245u;
|
|
uvec3 seed = uvec3(x, y, primitive_offset);
|
|
seed = ((seed >> 8u) ^ seed.yzx) * NOISE_PRIME;
|
|
seed = ((seed >> 8u) ^ seed.yzx) * NOISE_PRIME;
|
|
seed = ((seed >> 8u) ^ seed.yzx) * NOISE_PRIME;
|
|
seeded_noise = u16(seed.x >> 16u);
|
|
}
|
|
|
|
i16 noise_get_combiner()
|
|
{
|
|
return i16(((seeded_noise & U16_C(7u)) << U16_C(6u)) | U16_C(0x20u));
|
|
}
|
|
|
|
int noise_get_dither_alpha()
|
|
{
|
|
return int(seeded_noise & U16_C(7u));
|
|
}
|
|
|
|
int noise_get_dither_color()
|
|
{
|
|
// 3 bits of noise for RGB separately.
|
|
return int(seeded_noise & U16_C(0x1ff));
|
|
}
|
|
|
|
u8 noise_get_blend_threshold()
|
|
{
|
|
return u8(seeded_noise & U16_C(0xffu));
|
|
}
|
|
|
|
uvec3 noise_get_full_gamma_dither()
|
|
{
|
|
uint seed = seeded_noise;
|
|
return uvec3(seed & 0x3f, (seed >> 6u) & 0x3f, ((seed >> 9u) & 0x38) | (seed & 7u));
|
|
}
|
|
|
|
uvec3 noise_get_partial_gamma_dither()
|
|
{
|
|
return (uvec3(seeded_noise) >> uvec3(0, 1, 2)) & 1u;
|
|
}
|
|
|
|
#endif
|