citro3d/source/lightlut.c
2017-02-09 19:45:33 +01:00

66 lines
1.3 KiB
C

#include "internal.h"
void LightLut_FromArray(C3D_LightLut* lut, float* data)
{
int i;
for (i = 0; i < 256; i ++)
{
float in = data[i], diff = data[i+256];
u32 val = 0;
if (in > 0.0f)
{
in *= 0x1000;
val = (in < 0x1000) ? (u32)in : 0xFFF;
}
u32 val2 = 0;
if (diff != 0.0f)
{
if (diff < 0)
{
diff = -diff;
val2 = 0x800;
}
diff *= 0x800;
val2 |= (diff < 0x800) ? (u32)diff : 0x7FF;
}
lut->data[i] = val | (val2 << 12);
}
}
void LightLut_FromFunc(C3D_LightLut* lut, C3D_LightLutFunc func, float param, bool negative)
{
int i;
float data[512];
memset(data, 0, sizeof(data));
int start = negative ? (-127) : 0;
for (i = start; i < 128; i ++)
{
data[i & 0xFF] = func((float)i / 127.0f, param);
if (i != start) data[(i & 0xFF) + 255] = data[i & 0xFF] - data[(i-1) & 0xFF];
}
LightLut_FromArray(lut, data);
}
void LightLutDA_Create(C3D_LightLutDA* lut, C3D_LightLutFuncDA func, float from, float to, float arg0, float arg1)
{
int i;
float data[512];
data[511] = 0;
lut->scale = 1.0f / (to-from);
lut->bias = -from*lut->scale;
for (i = 0; i < 256; i ++)
{
float dist = ((float)i/255 - lut->bias) / lut->scale;
data[i] = func(dist, arg0, arg1);
if (i > 0)
data[i+255] = data[i]-data[i-1];
}
LightLut_FromArray(&lut->lut, data);
}