uint32_t val_rgb(float v)
{
uint32_t rgb = 0;
if (rainbow) {
float r = v * fminf(fmaxf(4.0f * v - 2.0f, 0.0f), 1.0f);
float g = v * fminf(fmaxf(1.0f - 4.0f * fabsf(v - 0.5f), 0.0f), 1.0f);
float b = v * fminf(fmaxf(2.0f - 4.0f * v, 0.0f), 1.0f);
rgb = srgb(r, g, b);
} else {
rgb = srgb(v, v, v);
}
return rgb;
}
uint32_t color(float v)
{
float r = 6.0f * fabsf(v - 3.0f / 6.0f) - 1.0f;
float g = 2.0f - 6.0f * fabsf(v - 2.0f / 6.0f);
float b = 2.0f - 6.0f * fabsf(v - 4.0f / 6.0f);
return srgb(r, g, b);
}
// Converts an HSV color to RGB and writes it to the output location with sRGB
// encoding. Assumes 'h', 's', and 'v' are on the interval [0,1].
static void hsv(unsigned char *out, double h, double s, double v) {
static int map[6][3] = {
{0, 3, 1}, {2, 0, 1}, {1, 0, 3}, {1, 2, 0}, {3, 1, 0}, {0, 1, 2}
};
double h6 = h * 6;
double f = h6 - (int)h6;
double vars[4] = {
v,
v * (1 - s),
v * (1 - (s * f)),
v * (1 - (s * (1 - f)))
};
int i = ((int)h6 % 6 + 6) % 6;
out[0] = srgb(vars[map[i][0]]);
out[1] = srgb(vars[map[i][1]]);
out[2] = srgb(vars[map[i][2]]);
}
void grayscale(unsigned char *out, double v) {
unsigned char g = srgb(v);
out[0] = g;
out[1] = g;
out[2] = g;
}
