#version 120 // "landmass" effect with forest construction using a geometry // shader. The landmass effect includes a bumpmap effect as well as // variation by altitude. // // The fragment shader needs position and normals in model and eye // coordinates. This vertex shader calculates the positions and // normals of the forest polygons so the geometry shader can do as // little as possible. // Input for the geometry shader. "raw" means terrain model // coordinates; that's a tile-local coordinate system, with z as local // up. "ec" means eye coordinates. // model position of original terrain poly; the bottom of the forest. varying vec4 rawposIn; // model normal varying vec3 NormalIn; varying vec4 ecPosIn; varying vec3 ecNormalIn; // eye spacce tangent and binormal varying vec3 VTangentIn; varying vec3 VBinormalIn; // screen-space position of top // constant color component varying vec4 constantColorIn; attribute vec3 tangent; attribute vec3 binormal; uniform float canopy_height; void main(void) { rawposIn = gl_Vertex; ecPosIn = gl_ModelViewMatrix * gl_Vertex; NormalIn = normalize(gl_Normal); //rawTopIn = rawposIn + vec4(0.0, 0.0, canopy_height, 0.0); //ecTopIn = gl_ModelViewMatrix * rawTopIn; ecNormalIn = gl_NormalMatrix * NormalIn; VTangentIn = gl_NormalMatrix * tangent; VBinormalIn = gl_NormalMatrix * binormal; gl_FrontColor = gl_Color; gl_Position = ftransform(); //positionTopIn = gl_ModelViewProjectionMatrix * rawTopIn; gl_TexCoord[0] = gl_TextureMatrix[0] * gl_MultiTexCoord0; constantColorIn = gl_FrontMaterial.emission + gl_Color * (gl_LightModel.ambient + gl_LightSource[0].ambient); }