Fix bump mapping

- Use tangent space normals from MDL
- Fix tangent space to world space transform

src/engine/graphics/mesh/mesh.cpp

@@ -95,13 +95,17 @@ void Mesh::init() {
         glEnableVertexAttribArray(5);
         glVertexAttribPointer(5, 3, GL_FLOAT, GL_FALSE, _attributes.stride, reinterpret_cast<void *>(_attributes.offBitangents));
     }
-    if (_attributes.offBoneIndices != -1) {
+    if (_attributes.offTanSpaceNormals != -1) {
         glEnableVertexAttribArray(6);
-        glVertexAttribPointer(6, 4, GL_FLOAT, GL_FALSE, _attributes.stride, reinterpret_cast<void *>(_attributes.offBoneIndices));
+        glVertexAttribPointer(6, 3, GL_FLOAT, GL_FALSE, _attributes.stride, reinterpret_cast<void *>(_attributes.offTanSpaceNormals));
+    }
+    if (_attributes.offBoneIndices != -1) {
+        glEnableVertexAttribArray(7);
+        glVertexAttribPointer(7, 4, GL_FLOAT, GL_FALSE, _attributes.stride, reinterpret_cast<void *>(_attributes.offBoneIndices));
     }
     if (_attributes.offBoneWeights != -1) {
-        glEnableVertexAttribArray(7);
-        glVertexAttribPointer(7, 4, GL_FLOAT, GL_FALSE, _attributes.stride, reinterpret_cast<void *>(_attributes.offBoneWeights));
+        glEnableVertexAttribArray(8);
+        glVertexAttribPointer(8, 4, GL_FLOAT, GL_FALSE, _attributes.stride, reinterpret_cast<void *>(_attributes.offBoneWeights));
     }
 
     glBindVertexArray(0);

src/engine/graphics/mesh/meshes.cpp

@@ -200,7 +200,7 @@ static const vector<uint16_t> g_aabbIndices = {
     6, 0, 0, 3, 3, 5, 5, 6
 };
 
-static const VertexAttributes g_aabbAttributes = { 3 * sizeof(float), 0, -1, -1, -1, -1, -1, -1, -1 };
+static const VertexAttributes g_aabbAttributes = { 3 * sizeof(float), 0 };
 
 // END AABB
 

src/engine/graphics/mesh/vertexattributes.h

@@ -31,6 +31,7 @@ struct VertexAttributes {
     int offTexCoords2 { -1 };
     int offTangents { -1 };
     int offBitangents { -1 };
+    int offTanSpaceNormals { -1 };
     int offBoneIndices { -1 };
     int offBoneWeights { -1 };
 };

src/engine/graphics/model/mdlreader.cpp

@@ -285,6 +285,7 @@ shared_ptr<ModelNode::TriangleMesh> MdlReader::readMesh(int flags) {
     if (offMdxTanSpace != -1) {
         attributes.offBitangents = offMdxTanSpace + 0 * sizeof(float);
         attributes.offTangents = offMdxTanSpace + 3 * sizeof(float);
+        attributes.offTanSpaceNormals = offMdxTanSpace + 6 * sizeof(float);
     }
 
     if (flags & NodeFlags::skin) {

src/engine/graphics/shader/shaders_common.cpp

@@ -239,7 +239,7 @@ vec3 getNormalFromBumpmap(vec2 uv) {
         result = normalize(result * 2.0 - 1.0);
     }
 
-    result = normalize(fragTanSpace * result);
+    result = normalize(result * fragTanSpace);
     return result;
 }
 
@@ -351,8 +351,9 @@ layout(location = 2) in vec2 aTexCoords;
 layout(location = 3) in vec2 aLightmapCoords;
 layout(location = 4) in vec3 aTangent;
 layout(location = 5) in vec3 aBitangent;
-layout(location = 6) in vec4 aBoneIndices;
-layout(location = 7) in vec4 aBoneWeights;
+layout(location = 6) in vec3 aTanSpaceNormal;
+layout(location = 7) in vec4 aBoneIndices;
+layout(location = 8) in vec4 aBoneWeights;
 
 out vec3 fragPosition;
 out vec3 fragNormal;
@@ -362,8 +363,8 @@ out vec4 fragPosLightSpace;
 out mat3 fragTanSpace;
 
 void main() {
-    vec4 P = vec4(aPosition, 1.0);
-    vec4 N = vec4(aNormal, 0.0);
+    vec4 position = vec4(aPosition, 1.0);
+    vec4 normal = vec4(aNormal, 0.0);
 
     if (isFeatureEnabled(FEATURE_SKELETAL)) {
         int i1 = int(aBoneIndices[0]);
@@ -376,32 +377,38 @@ void main() {
         float w3 = aBoneWeights[2];
         float w4 = aBoneWeights[3];
 
-        P =
-            (uBones[i1] * P) * w1 +
-            (uBones[i2] * P) * w2 +
-            (uBones[i3] * P) * w3 +
-            (uBones[i4] * P) * w4;
+        position =
+            (uBones[i1] * position) * w1 +
+            (uBones[i2] * position) * w2 +
+            (uBones[i3] * position) * w3 +
+            (uBones[i4] * position) * w4;
 
-        N =
-            (uBones[i1] * N) * w1 +
-            (uBones[i2] * N) * w2 +
-            (uBones[i3] * N) * w3 +
-            (uBones[i4] * N) * w4;
+        normal =
+            (uBones[i1] * normal) * w1 +
+            (uBones[i2] * normal) * w2 +
+            (uBones[i3] * normal) * w3 +
+            (uBones[i4] * normal) * w4;
 
     } else if (isFeatureEnabled(FEATURE_DANGLYMESH)) {
         vec3 maxStride = vec3(uDanglymeshDisplacement * uDanglymeshConstraints[gl_VertexID / 4][gl_VertexID % 4]);
         vec3 stride = clamp(uDanglymeshStride.xyz, -maxStride, maxStride);
-        P += vec4(stride, 0.0);
+        position += vec4(stride, 0.0);
     }
 
     mat3 normalMatrix = transpose(inverse(mat3(uGeneral.model)));
-    N = vec4(normalize(normalMatrix * N.xyz), 0.0);
 
-    fragPosition = vec3(uGeneral.model * P);
-    fragNormal = N.xyz;
+    fragPosition = vec3(uGeneral.model * position);
+    fragNormal = normalize(normalMatrix * normal.xyz);
     fragTexCoords = aTexCoords;
     fragLightmapCoords = aLightmapCoords;
 
+    if (isFeatureEnabled(FEATURE_BUMPMAPS)) {
+        vec3 T = normalize(normalMatrix * aTangent);
+        vec3 B = normalize(normalMatrix * aBitangent);
+        vec3 N = normalize(normalMatrix * aTanSpaceNormal);
+        fragTanSpace = transpose(mat3(T, B, N));
+    }
+
     // Compute light space fragment position for directional lights
     if (uShadows.lightPresent && uShadows.lightPosition.w == 0.0) {
         fragPosLightSpace = uShadows.lightSpaceMatrices[0] * vec4(fragPosition, 1.0);
@@ -409,12 +416,6 @@ void main() {
         fragPosLightSpace = vec4(0.0);
     }
 
-    if (isFeatureEnabled(FEATURE_BUMPMAPS)) {
-        vec3 T = normalize(normalMatrix * aTangent);
-        vec3 B = normalize(normalMatrix * aBitangent);
-        fragTanSpace = transpose(mat3(T, B, N));
-    }
-
     gl_Position = uGeneral.projection * uGeneral.view * vec4(fragPosition, 1.0);
 }
 )END";