mirror of
https://github.com/luanti-org/luanti.git
synced 2025-11-04 01:05:48 +01:00
e0d4a9d575
- Make volumetric light effect strength server controllable - Separate volumetric and bloom shader pipeline - Require bloom to be enable, scale godrays with bloom
116 lines
3.7 KiB
GLSL
116 lines
3.7 KiB
GLSL
#define rendered texture0
|
|
#define depthmap texture1
|
|
|
|
uniform sampler2D rendered;
|
|
uniform sampler2D depthmap;
|
|
|
|
uniform vec3 sunPositionScreen;
|
|
uniform float sunBrightness;
|
|
uniform vec3 moonPositionScreen;
|
|
uniform float moonBrightness;
|
|
|
|
uniform lowp float volumetricLightStrength;
|
|
|
|
uniform vec3 dayLight;
|
|
#ifdef ENABLE_DYNAMIC_SHADOWS
|
|
uniform vec3 v_LightDirection;
|
|
#else
|
|
const vec3 v_LightDirection = vec3(0.0, -1.0, 0.0);
|
|
#endif
|
|
|
|
#ifdef GL_ES
|
|
varying mediump vec2 varTexCoord;
|
|
#else
|
|
centroid varying vec2 varTexCoord;
|
|
#endif
|
|
|
|
const float far = 1000.;
|
|
float mapDepth(float depth)
|
|
{
|
|
return min(1., 1. / (1.00001 - depth) / far);
|
|
}
|
|
|
|
float noise(vec3 uvd) {
|
|
return fract(dot(sin(uvd * vec3(13041.19699, 27723.29171, 61029.77801)), vec3(73137.11101, 37312.92319, 10108.89991)));
|
|
}
|
|
|
|
float sampleVolumetricLight(vec2 uv, vec3 lightVec, float rawDepth)
|
|
{
|
|
lightVec = 0.5 * lightVec / lightVec.z + 0.5;
|
|
const float samples = 30.;
|
|
float result = texture2D(depthmap, uv).r < 1. ? 0.0 : 1.0;
|
|
float bias = noise(vec3(uv, rawDepth));
|
|
vec2 samplepos;
|
|
for (float i = 1.; i < samples; i++) {
|
|
samplepos = mix(uv, lightVec.xy, (i + bias) / samples);
|
|
if (min(samplepos.x, samplepos.y) > 0. && max(samplepos.x, samplepos.y) < 1.)
|
|
result += texture2D(depthmap, samplepos).r < 1. ? 0.0 : 1.0;
|
|
}
|
|
return result / samples;
|
|
}
|
|
|
|
vec3 getDirectLightScatteringAtGround(vec3 v_LightDirection)
|
|
{
|
|
// Based on talk at 2002 Game Developers Conference by Naty Hoffman and Arcot J. Preetham
|
|
const float beta_r0 = 1e-5; // Rayleigh scattering beta
|
|
|
|
// These factors are calculated based on expected value of scattering factor of 1e-5
|
|
// for Nitrogen at 532nm (green), 2e25 molecules/m3 in atmosphere
|
|
const vec3 beta_r0_l = vec3(3.3362176e-01, 8.75378289198826e-01, 1.95342379700656) * beta_r0; // wavelength-dependent scattering
|
|
|
|
const float atmosphere_height = 15000.; // height of the atmosphere in meters
|
|
// sun/moon light at the ground level, after going through the atmosphere
|
|
return exp(-beta_r0_l * atmosphere_height / (1e-5 - dot(v_LightDirection, vec3(0., 1., 0.))));
|
|
}
|
|
|
|
vec3 applyVolumetricLight(vec3 color, vec2 uv, float rawDepth)
|
|
{
|
|
vec3 lookDirection = normalize(vec3(uv.x * 2. - 1., uv.y * 2. - 1., rawDepth));
|
|
|
|
const float boost = 4.0;
|
|
float brightness = 0.;
|
|
vec3 sourcePosition = vec3(-1., -1., -1);
|
|
|
|
if (sunPositionScreen.z > 0. && sunBrightness > 0.) {
|
|
brightness = sunBrightness;
|
|
sourcePosition = sunPositionScreen;
|
|
}
|
|
else if (moonPositionScreen.z > 0. && moonBrightness > 0.) {
|
|
brightness = moonBrightness * 0.05;
|
|
sourcePosition = moonPositionScreen;
|
|
}
|
|
|
|
float cameraDirectionFactor = pow(clamp(dot(sourcePosition, vec3(0., 0., 1.)), 0.0, 0.7), 2.5);
|
|
float viewAngleFactor = pow(max(0., dot(sourcePosition, lookDirection)), 8.);
|
|
|
|
float lightFactor = brightness * sampleVolumetricLight(uv, sourcePosition, rawDepth) *
|
|
(0.05 * cameraDirectionFactor + 0.95 * viewAngleFactor);
|
|
|
|
color = mix(color, boost * getDirectLightScatteringAtGround(v_LightDirection) * dayLight, lightFactor);
|
|
|
|
// a factor of 5 tested well
|
|
color *= volumetricLightStrength * 5.0;
|
|
|
|
// if (sunPositionScreen.z < 0.)
|
|
// color.rg += 1. - clamp(abs((2. * uv.xy - 1.) - sunPositionScreen.xy / sunPositionScreen.z) * 1000., 0., 1.);
|
|
// if (moonPositionScreen.z < 0.)
|
|
// color.rg += 1. - clamp(abs((2. * uv.xy - 1.) - moonPositionScreen.xy / moonPositionScreen.z) * 1000., 0., 1.);
|
|
return color;
|
|
}
|
|
|
|
void main(void)
|
|
{
|
|
vec2 uv = varTexCoord.st;
|
|
vec3 color = texture2D(rendered, uv).rgb;
|
|
// translate to linear colorspace (approximate)
|
|
color = pow(color, vec3(2.2));
|
|
|
|
if (volumetricLightStrength > 0.0) {
|
|
float rawDepth = texture2D(depthmap, uv).r;
|
|
|
|
color = applyVolumetricLight(color, uv, rawDepth);
|
|
}
|
|
|
|
gl_FragColor = vec4(color, 1.0); // force full alpha to avoid holes in the image.
|
|
}
|