1
0
Fork 0
fgdata/Shaders/planet-cloudlayer.frag

81 lines
2.3 KiB
C++

// -*-C++-*-
// Ambient term comes in gl_Color.rgb.
#version 120
varying vec4 diffuse_term;
varying vec3 normal;
varying vec3 ecViewDir;
varying vec3 VTangent;
uniform bool use_overlay;
uniform sampler2D texture;
uniform sampler2D structure_texture;
float Noise2D(in vec2 coord, in float wavelength);
void main()
{
vec3 n;
float NdotL, NdotHV;
vec4 color = gl_Color;
vec3 lightDir = gl_LightSource[0].position.xyz;
vec3 halfVector = normalize(normalize(lightDir) + normalize(ecViewDir));
vec4 texel;
vec4 structureTexel;
vec4 fragColor;
vec4 specular = vec4(0.0);
// If gl_Color.a == 0, this is a back-facing polygon and the
// normal should be reversed.
n = (2.0 * gl_Color.a - 1.0) * normal;
n = normalize(n);
vec3 light_specular = vec3 (1.0, 1.0, 1.0);
NdotL = dot(n, lightDir);
NdotL = smoothstep(-0.2,0.2,NdotL);
float intensity = length(diffuse_term);
vec4 dawn = intensity * normalize (vec4 (1.0,0.4,0.4,1.0));
vec4 diff_term = mix(dawn, diffuse_term, smoothstep(0.0, 0.2, NdotL));
if (NdotL > 0.0) {
color += diffuse_term * NdotL ;
NdotHV = max(dot(n, halfVector), 0.0);
if (gl_FrontMaterial.shininess > 0.0)
specular.rgb = (gl_FrontMaterial.specular.rgb
* light_specular
* pow(NdotHV, gl_FrontMaterial.shininess));
}
color.a = diffuse_term.a;
// This shouldn't be necessary, but our lighting becomes very
// saturated. Clamping the color before modulating by the texture
// is closer to what the OpenGL fixed function pipeline does.
color = clamp(color, 0.0, 1.0);
texel = texture2D(texture, gl_TexCoord[0].st);
structureTexel = texture2D(structure_texture, 20.0 * gl_TexCoord[0].st);
float noise = Noise2D( gl_TexCoord[0].st, 0.01);
noise += Noise2D( gl_TexCoord[0].st, 0.005);
noise += Noise2D( gl_TexCoord[0].st, 0.002);
//vec4 noiseTexel = vec4 (1.0,1.0,1.0, smoothstep(0.3,1.2,noise) * texel.a);
vec4 noiseTexel = vec4 (1.0,1.0,1.0, 0.5* noise * texel.a);
structureTexel = mix(structureTexel, noiseTexel,noiseTexel.a);
if (use_overlay)
{
texel = vec4(structureTexel.rgb, texel.a * structureTexel.a);
}
fragColor = color * texel + specular;
gl_FragColor = fragColor;
}