1uniform sampler2D m_Texture; 2uniform sampler2D m_DepthTexture; 3varying vec2 texCoord; 4 5uniform vec4 m_FogColor; 6uniform float m_FogDensity; 7uniform float m_FogDistance; 8 9vec2 m_FrustumNearFar=vec2(1.0,m_FogDistance); 10const float LOG2 = 1.442695; 11 12void main() { 13 vec4 texVal = texture2D(m_Texture, texCoord); 14 float fogVal =texture2D(m_DepthTexture,texCoord).r; 15 float depth= (2.0 * m_FrustumNearFar.x) / (m_FrustumNearFar.y + m_FrustumNearFar.x - fogVal* (m_FrustumNearFar.y-m_FrustumNearFar.x)); 16 17 float fogFactor = exp2( -m_FogDensity * m_FogDensity * depth * depth * LOG2 ); 18 fogFactor = clamp(fogFactor, 0.0, 1.0); 19 gl_FragColor =mix(m_FogColor,texVal,fogFactor); 20 21}