Change normal bias for entities to avoid shadow acne

diff --git a/client/shaders/object_shader/opengl_fragment.glsl b/client/shaders/object_shader/opengl_fragment.glsl
index 48066adc34a4bde24ac9efc9b7724f513fe73e17..fdfcec0c8928c0913b4c223f30f173955618ec2f 100644 (file)
--- a/client/shaders/object_shader/opengl_fragment.glsl
+++ b/client/shaders/object_shader/opengl_fragment.glsl
@@ -56,12 +56,6 @@ vec4 getPerspectiveFactor(in vec4 shadowPosition)
        return shadowPosition;
 }
 
-// assuming near is always 1.0
-float getLinearDepth()
-{
-       return 2.0 * f_shadowfar / (f_shadowfar + 1.0 - (2.0 * gl_FragCoord.z - 1.0) * (f_shadowfar - 1.0));
-}
-
 vec3 getLightSpacePosition()
 {
        vec4 pLightSpace;
@@ -69,8 +63,7 @@ vec3 getLightSpacePosition()
        #if DRAW_TYPE == NDT_PLANTLIKE
        pLightSpace = m_ShadowViewProj * vec4(worldPosition, 1.0);
        #else
-       float offsetScale = (0.0057 * getLinearDepth() + normalOffsetScale);
-       pLightSpace = m_ShadowViewProj * vec4(worldPosition + offsetScale * normalize(vNormal), 1.0);
+       pLightSpace = m_ShadowViewProj * vec4(worldPosition + normalOffsetScale * normalize(vNormal), 1.0);
        #endif
        pLightSpace = getPerspectiveFactor(pLightSpace);
        return pLightSpace.xyz * 0.5 + 0.5;
@@ -544,6 +537,5 @@ void main(void)
        float clarity = clamp(fogShadingParameter
                - fogShadingParameter * length(eyeVec) / fogDistance, 0.0, 1.0);
        col = mix(skyBgColor, col, clarity);
-
        gl_FragColor = vec4(col.rgb, base.a);
 }

diff --git a/client/shaders/object_shader/opengl_vertex.glsl b/client/shaders/object_shader/opengl_vertex.glsl
index 9ca5ef0f38993b615d9d364d6723fd746932326c..12078f532e251a669ce651e757f483aca2154c83 100644 (file)
--- a/client/shaders/object_shader/opengl_vertex.glsl
+++ b/client/shaders/object_shader/opengl_vertex.glsl
@@ -36,6 +36,8 @@ const vec3 artificialLight = vec3(1.04, 1.04, 1.04);
 varying float vIDiff;
 const float e = 2.718281828459;
 const float BS = 10.0;
+const float bias0 = 0.9;
+const float bias1 = 1.0 - bias0;
 
 #ifdef ENABLE_DYNAMIC_SHADOWS
 // custom smoothstep implementation because it's not defined in glsl1.2
@@ -104,8 +106,15 @@ void main(void)
 #ifdef ENABLE_DYNAMIC_SHADOWS
        vec3 nNormal = normalize(vNormal);
        cosLight = dot(nNormal, -v_LightDirection);
-       float texelSize = 767.0 / f_textureresolution;
-       float slopeScale = clamp(1.0 - abs(cosLight), 0.0, 1.0);
+
+       // Calculate normal offset scale based on the texel size adjusted for 
+       // curvature of the SM texture. This code must be change together with
+       // getPerspectiveFactor or any light-space transformation.
+       float distanceToPlayer = length((eyePosition - worldPosition).xyz) / f_shadowfar;
+       float perspectiveFactor = distanceToPlayer * bias0 + bias1;
+       float texelSize = 1.0 / f_textureresolution;
+       texelSize *= f_shadowfar * perspectiveFactor / (bias1 / perspectiveFactor - texelSize * bias0) * 0.15;
+       float slopeScale = clamp(pow(1.0 - cosLight*cosLight, 0.5), 0.0, 1.0);
        normalOffsetScale = texelSize * slopeScale;
        
        if (f_timeofday < 0.2) {