rbdlsim/3rdparty/tracy/extra/color.cpp

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2021-08-06 12:10:32 +02:00
#include <algorithm>
#include <string.h>
#include <stdio.h>
#include <stdint.h>
#include <math.h>
inline float sqrtfast( float v )
{
union
{
int i;
float f;
} u;
u.f = v;
u.i -= 1 << 23;
u.i >>= 1;
u.i += 1 << 29;
return u.f;
}
inline float linear2sRGB( float v )
{
float s1 = sqrtfast( v );
float s2 = sqrtfast( s1 );
float s3 = sqrtfast( s2 );
return 0.585122381f * s1 + 0.783140355f * s2 - 0.368262736f * s3;
}
int lerp( int v0, int v1, float t )
{
return int( ( 1-t ) * v0 + t * v1 );
}
inline float sRGB2linear( float v )
{
return v * ( v * ( v * 0.305306011f + 0.682171111f ) + 0.012522878f );
}
int main()
{
int c0 = std::min( 255, int( sRGB2linear( 1.f ) * 255 ) );
int c1 = std::min( 255, int( sRGB2linear( 0x44 / 255.f ) * 255 ) );
int s0 = std::min( 255, int( sRGB2linear( 1.f ) * 255 * 0.5 ) );
int s1 = std::min( 255, int( sRGB2linear( 0x44 / 255.f ) * 255 * 0.5 ) );
float target = 80.f;
uint32_t t[256];
memset( t, 0, sizeof( uint32_t ) * 256 );
for( int i=1; i<128; i++ )
{
float m = (i-1) / target;
int l0 = std::min( 255, lerp( s0, c0, m ) );
int l1 = std::min( 255, lerp( s1, c1, m ) );
int g0 = std::min( 255, int( linear2sRGB( l0/255.f ) * 255 ) );
int g1 = std::min( 255, int( linear2sRGB( l1/255.f ) * 255 ) );
g0 = l0;
g1 = l1;
t[i] = 0xFF000000 | ( g1 << 16 ) | ( g0 << 8 ) | g1;
t[uint8_t(-i)] = 0xFF000000 | ( g1 << 16 ) | ( g1 << 8 ) | g0;
}
printf( "uint32_t MemDecayColor[256] = {\n" );
for( int i=0; i<256; i += 8 )
{
printf( " " );
for( int j=i; j<i+8; j++ )
{
printf( " 0x%X,", t[j] );
}
printf( "\n" );
}
printf( "};\n" );
}