Add parallax mapping for objects

components/resource/scenemanager.cpp

@@ -385,6 +385,7 @@ namespace Resource
             shaderVisitor.setForcePerPixelLighting(mForcePerPixelLighting);
             shaderVisitor.setAutoUseNormalMaps(mAutoUseNormalMaps);
             shaderVisitor.setNormalMapPattern(mNormalMapPattern);
+            shaderVisitor.setNormalHeightMapPattern(mNormalHeightMapPattern);
             shaderVisitor.setAutoUseSpecularMaps(mAutoUseSpecularMaps);
             shaderVisitor.setSpecularMapPattern(mSpecularMapPattern);
             loaded->accept(shaderVisitor);

components/shader/shadervisitor.cpp

@@ -284,6 +284,8 @@ namespace Shader
         defineMap["forcePPL"] = mForcePerPixelLighting ? "1" : "0";
         defineMap["clamp"] = mClampLighting ? "1" : "0";
 
+        defineMap["parallax"] = reqs.mNormalHeight ? "1" : "0";
+
         osg::ref_ptr<osg::Shader> vertexShader (mShaderManager.getShader(mDefaultVsTemplate, defineMap, osg::Shader::VERTEX));
         osg::ref_ptr<osg::Shader> fragmentShader (mShaderManager.getShader(mDefaultFsTemplate, defineMap, osg::Shader::FRAGMENT));
 
@@ -376,6 +378,11 @@ namespace Shader
         mNormalMapPattern = pattern;
     }
 
+    void ShaderVisitor::setNormalHeightMapPattern(const std::string &pattern)
+    {
+        mNormalHeightMapPattern = pattern;
+    }
+
     void ShaderVisitor::setAutoUseSpecularMaps(bool use)
     {
         mAutoUseSpecularMaps = use;

files/shaders/objects_fragment.glsl

@@ -54,12 +54,46 @@ varying vec4 passColor;
 varying vec3 passViewPos;
 varying vec3 passNormal;
 
+#if @parallax
+uniform mat4 osg_ViewMatrixInverse;
+#endif
+
 #include "lighting.glsl"
+#include "parallax.glsl"
 
 void main()
 {
+    vec2 adjustedDiffuseUV = diffuseMapUV;
+
+#if @normalMap
+    vec4 normalTex = texture2D(normalMap, normalMapUV);
+
+    vec3 normalizedNormal = normalize(passNormal);
+    vec3 normalizedTangent = normalize(passTangent);
+    vec3 binormal = cross(normalizedTangent, normalizedNormal);
+    mat3 tbn = mat3(normalizedTangent, binormal, normalizedNormal);
+
+    vec3 viewNormal = gl_NormalMatrix * normalize(tbn * (normalTex.xyz * 2.0 - 1.0));
+#else
+    vec3 viewNormal = gl_NormalMatrix * normalize(passNormal);
+#endif
+
+#if @parallax
+    vec3 cameraPos = osg_ViewMatrixInverse[3].xyz;
+    vec3 eyeDir = normalize(cameraPos - (osg_ViewMatrixInverse * vec4(passViewPos, 1)).xyz);
+    vec2 offset = getParallaxOffset(eyeDir, tbn, normalTex.a);
+    adjustedDiffuseUV += offset; // only offset diffuse for now, other textures are more likely to be using a completely different UV set
+
+#if @diffuseMapUV == @normalMapUV
+    // fetch a new normal using updated coordinates
+    normalTex = texture2D(normalMap, adjustedDiffuseUV);
+    viewNormal = gl_NormalMatrix * normalize(tbn * (normalTex.xyz * 2.0 - 1.0));
+#endif
+
+#endif
+
 #if @diffuseMap
-    gl_FragData[0] = texture2D(diffuseMap, diffuseMapUV);
+    gl_FragData[0] = texture2D(diffuseMap, adjustedDiffuseUV);
 #else
     gl_FragData[0] = vec4(1.0, 1.0, 1.0, 1.0);
 #endif
@@ -77,20 +111,6 @@ void main()
     gl_FragData[0].xyz = mix(gl_FragData[0].xyz, decalTex.xyz, decalTex.a);
 #endif
 
-#if @normalMap
-    vec3 normalTex = texture2D(normalMap, normalMapUV).xyz;
-
-    vec3 normalizedNormal = normalize(passNormal);
-    vec3 normalizedTangent = normalize(passTangent);
-    vec3 binormal = cross(normalizedTangent, normalizedNormal);
-    mat3 tbn = mat3(normalizedTangent, binormal, normalizedNormal);
-
-    vec3 viewNormal = gl_NormalMatrix * normalize(tbn * (normalTex * 2.0 - 1.0));
-#else
-    vec3 viewNormal = gl_NormalMatrix * normalize(passNormal);
-#endif
-
-
 #if !PER_PIXEL_LIGHTING
     gl_FragData[0] *= lighting;
 #else