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fgdata/Shaders/planet.frag
2015-12-07 08:43:58 +02:00

132 lines
4.2 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 float visibility;
uniform float sun_angle;
uniform bool use_clouds;
uniform bool use_cloud_shadows;
uniform bool use_overlay;
uniform sampler2D texture;
uniform sampler2D shadowtex;
uniform sampler2D grain_texture;
float Noise2D(in vec2 coord, in float wavelength);
float luminance(vec3 color)
{
return dot(vec3(0.212671, 0.715160, 0.072169), color);
}
void main()
{
vec3 n;
float NdotL, NdotHV;
vec4 color = gl_Color;
vec3 lightDir = normalize(gl_LightSource[0].position.xyz);
vec3 halfVector = normalize(lightDir + normalize(ecViewDir));
vec4 texel;
vec4 shadowTexel;
vec4 grainTexel;
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 VBinormal;
VBinormal = cross(normal, VTangent);
float xOffset = -0.005 * dot(lightDir, normalize(VTangent));
float yOffset = -0.005 * dot(lightDir, normalize(VBinormal));
if ((use_cloud_shadows)&&(use_clouds))
{shadowTexel = texture2D(shadowtex, vec2(gl_TexCoord[0].s-xOffset, gl_TexCoord[0].t-yOffset));}
else
{shadowTexel = vec4 (0.0,0.0,0.0,0.0);}
texel = texture2D(texture, gl_TexCoord[0].st);
grainTexel = texture2D(grain_texture, gl_TexCoord[0].st * 40.0);
float noise = Noise2D( gl_TexCoord[0].st, 0.00005);
noise += Noise2D( gl_TexCoord[0].st, 0.0002);
noise += Noise2D( gl_TexCoord[0].st, 0.0001);
noise= noise/3.0;
vec3 light_specular = vec3 (1.0, 1.0, 1.0);
NdotL = dot(n, lightDir);
// due to atmosphere scattering, we should make this harder
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));
intensity = length(light_specular);
light_specular = mix(dawn.rgb, light_specular, smoothstep(0.0, 0.2, NdotL));
float oceanness = smoothstep(0.0, 0.1,length(texel.rgb - vec3 (0.007,0.019, 0.078)));
float specular_enhancement = 4.0 * (1.0 - oceanness);
if (use_overlay) {
//texel.rgb = mix(texel.rgb, grainTexel.rgb, 0.4* grainTexel.a * oceanness);
texel.rgb = texel.rgb * (0.85 + 0.3 * noise);
texel.r = smoothstep(0.0, 0.95, texel.r);
texel.g = smoothstep(0.0, 0.95, texel.g);
texel.b = smoothstep(0.0, 0.95, texel.b);
float intensity = length(texel.rgb);
texel.rgb = mix(texel.rgb, intensity * vec3 (1.0,1.0,1.0), 0.3);
}
//texel.rgb = vec3 (0.5,0.5,0.5);
if (NdotL > 0.0) {
color += diffuse_term * NdotL * (1.0-shadowTexel.a);
NdotHV = max(dot(n, halfVector), 0.0);
if (gl_FrontMaterial.shininess > 0.0)
specular.rgb = (gl_FrontMaterial.specular.rgb * specular_enhancement
* light_specular * (1.0-shadowTexel.a)
* 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);
fragColor = color * texel + specular;
//fragColor = fragColor * (1.0 - 0.5 * shadowTexel.a);
//fragColor = mix(fragColor, shadowTexel, shadowTexel.a);
float angle = dot(normalize(ecViewDir), normalize(normal));
float distance_through_atmosphere = min(10.0 / (abs(angle)+0.001),500.0);
float correction = smoothstep(-0.4, 0.0, dot(n, lightDir) - 0.45 ) ;
correction = correction + (1.0 - correction) * (1.0 - smoothstep(1.40, 1.57, sun_angle));
float correction1 = 1.0 - smoothstep(1.4, 1.45, sun_angle);
vec4 fogColor = vec4 (0.83,0.9,1.0,1.0) * clamp(length(diffuse_term.rgb/1.73 * correction * clamp(NdotL + correction1,0.01, 0.99) ),0.0,1.0);
float fogFactor = exp(-distance_through_atmosphere/(visibility/1000.0));
fragColor = mix(fogColor, fragColor, fogFactor);
gl_FragColor = fragColor;
//gl_FragColor = vec4 (NdotL - 0.5, NdotL - 0.5, NdotL - 0.5, 1.0);
}