Sergey Sharybin
7bce3dd3ad
Seems to be a division by zero error. Should be safe for an upcoming 'a' release.
49 lines
1.1 KiB
GLSL
49 lines
1.1 KiB
GLSL
|
|
varying vec3 coords;
|
|
|
|
uniform vec3 active_color;
|
|
uniform float step_size;
|
|
uniform float density_scale;
|
|
|
|
uniform sampler3D soot_texture;
|
|
uniform sampler3D shadow_texture;
|
|
|
|
#ifdef USE_FIRE
|
|
uniform sampler3D flame_texture;
|
|
uniform sampler1D spectrum_texture;
|
|
#endif
|
|
|
|
void main()
|
|
{
|
|
/* compute color and density from volume texture */
|
|
vec4 soot = texture3D(soot_texture, coords);
|
|
vec3 soot_color;
|
|
if (soot.a != 0) {
|
|
soot_color = active_color * soot.rgb / soot.a;
|
|
}
|
|
else {
|
|
soot_color = vec3(0, 0, 0);
|
|
}
|
|
float soot_density = density_scale * soot.a;
|
|
|
|
/* compute transmittance and alpha */
|
|
float soot_transmittance = pow(2.71828182846, -soot_density * step_size);
|
|
float soot_alpha = 1.0 - soot_transmittance;
|
|
|
|
/* shade */
|
|
float shadow = texture3D(shadow_texture, coords).r;
|
|
soot_color *= soot_transmittance * shadow;
|
|
|
|
/* premultiply alpha */
|
|
vec4 color = vec4(soot_alpha * soot_color, soot_alpha);
|
|
|
|
#ifdef USE_FIRE
|
|
/* fire */
|
|
float flame = texture3D(flame_texture, coords).r;
|
|
vec4 emission = texture1D(spectrum_texture, flame);
|
|
color.rgb += (1 - color.a) * emission.a * emission.rgb;
|
|
#endif
|
|
|
|
gl_FragColor = color;
|
|
}
|