使用RenderMonkey:
从自带的sobel修改的。
vertex:
uniform float height; varying vec4 vTexCoords00; varying vec4 vTexCoords01; varying vec4 vTexCoords02; varying vec4 vTexCoords10; varying vec4 vTexCoords11; varying vec4 vTexCoords12; varying vec4 vTexCoords20; varying vec4 vTexCoords21; varying vec4 vTexCoords22; void main(void) { vec4 Pos = gl_Vertex; gl_Position = vec4(Pos.xy,, ); vec4 BaseTexCoord; BaseTexCoord.x = 0.5 * (1.0 - Pos.x); BaseTexCoord.y = 0.5 * (1.0 + Pos.y); BaseTexCoord.zw = vec2(0.0, 1.0); float vOffset = (1.0 / height); vTexCoords00 = BaseTexCoord + vec4(-vOffset, -vOffset, 0.0, 0.0); vTexCoords01 = BaseTexCoord + vec4( 0.0, -vOffset, 0.0, 0.0); vTexCoords02 = BaseTexCoord + vec4( vOffset, -vOffset, 0.0, 0.0); vTexCoords10 = BaseTexCoord + vec4(-vOffset, 0.0, 0.0, 0.0); vTexCoords11 = BaseTexCoord; vTexCoords12 = BaseTexCoord + vec4( vOffset, 0.0, 0.0, 0.0); vTexCoords20 = BaseTexCoord + vec4(-vOffset, vOffset, 0.0, 0.0); vTexCoords21 = BaseTexCoord + vec4( 0.0, vOffset, 0.0, 0.0); vTexCoords22 = BaseTexCoord + vec4( vOffset, vOffset, 0.0, 0.0); }
Fragment:
uniform sampler2D BaseMap; varying vec4 vTexCoords00; varying vec4 vTexCoords01; varying vec4 vTexCoords02; varying vec4 vTexCoords10; varying vec4 vTexCoords11; varying vec4 vTexCoords12; varying vec4 vTexCoords20; varying vec4 vTexCoords21; varying vec4 vTexCoords22; void main(void) { vec4 s00; vec4 s01; vec4 s02; vec4 s10; vec4 s11; vec4 s12; vec4 s20; vec4 s21; vec4 s22; s00 = texture2DProj(BaseMap, vTexCoords00); s01 = texture2DProj(BaseMap, vTexCoords01); s02 = texture2DProj(BaseMap, vTexCoords02); s10 = texture2DProj(BaseMap, vTexCoords10); s11= texture2DProj(BaseMap, vTexCoords11); s12 = texture2DProj(BaseMap, vTexCoords12); s20 = texture2DProj(BaseMap, vTexCoords20); s21 = texture2DProj(BaseMap, vTexCoords21); s22 = texture2DProj(BaseMap, vTexCoords22); vec4 re=s00*0.0625+s01*0.125+s02*0.0625+ s10*0.1250+s11*0.250+s12*0.1250+ s20*0.0625+s21*0.125+s22*0.0625; gl_FragColor = re; }