1
0
Fork 0
fgdata/Shaders/forest.frag
2010-08-21 13:10:19 +02:00

72 lines
2 KiB
GLSL

#version 120
varying vec4 rawpos;
varying vec4 ecPosition;
varying vec3 VNormal;
varying vec3 Normal;
uniform sampler3D NoiseTex;
uniform sampler2D SampleTex;
uniform sampler1D ColorsTex;
uniform sampler2D SampleTex2;
const float scale = 1.0;
void main (void)
{
const float snowlevel=2000.0;
vec4 basecolor = texture2D(SampleTex, rawpos.xy*0.000144);
vec4 basecolor2 = texture2D(SampleTex2, rawpos.xy*0.000144);
basecolor = texture1D(ColorsTex, basecolor.r+0.0);
vec4 noisevec = texture3D(NoiseTex, (rawpos.xyz)*0.01*scale);
vec4 nvL = texture3D(NoiseTex, (rawpos.xyz)*0.00066*scale);
float fogFactor;
float fogCoord = ecPosition.z;
const float LOG2 = 1.442695;
fogFactor = exp2(-gl_Fog.density * gl_Fog.density * fogCoord * fogCoord * LOG2);
float biasFactor = exp2(-0.00000002 * fogCoord * fogCoord * LOG2);
float n=0.12;
n += nvL[0]*0.4;
n += nvL[1]*0.6;
n += nvL[2]*2.0;
n += nvL[3]*4.0;
n += noisevec[0]*0.1;
n += noisevec[1]*0.4;
n += noisevec[2]*0.8;
n += noisevec[3]*2.1;
n = mix(0.6, n, biasFactor);
vec4 c1;
c1 = basecolor * vec4(smoothstep(-1.3, 0.5, n), smoothstep(-1.3, 0.5, n), smoothstep(-2.0, 0.9, n), 0.0);
vec4 c2;
c2 = basecolor2 * vec4(smoothstep(-1.3, 0.5, n), smoothstep(-1.3, 0.5, n), smoothstep(-2.0, 0.9, n), 0.0);
//draw floor where !steep, and another blurb for smoothing transitions
vec4 c3, c4, c5;
c3 = mix(vec4(n-0.88, n-0.14, -n, 0.0), c1, smoothstep(0.990, 0.970, abs(normalize(Normal).z)+nvL[2]*1.3));
c4 = mix(vec4(n-0.88, n-0.74, -n, 0.0), c1, smoothstep(0.990, 0.890, abs(normalize(Normal).z)+nvL[2]*0.9));
c5 = mix(c3, c4, 1.0);
//mix floor with texture right way
c1 = mix(c2, c5, clamp(0.65, n*0.5, 0.4));
vec3 diffuse = gl_Color.rgb * max(0.4, dot(VNormal, gl_LightSource[0].position.xyz));
vec4 ambient_light = gl_LightSource[0].diffuse * vec4(diffuse, 1.0);
c1 *= ambient_light;
vec4 finalColor = c1;
if(gl_Fog.density == 1.0)
fogFactor=1.0;
gl_FragColor = mix(gl_Fog.color ,finalColor, fogFactor);
}