Support 4 components mesh.tangent data

Added struct Vector4 for convenience

src/models.c

@@ -2329,12 +2329,12 @@ static Mesh LoadOBJ(const char *fileName)
     else
     {
         // Attempt to calculate mesh tangents and binormals using positions and texture coordinates
-        mesh.tangents = (float *)malloc(mesh.vertexCount*3*sizeof(float));
+        mesh.tangents = (float *)malloc(mesh.vertexCount*4*sizeof(float));
         // mesh.binormals = (float *)malloc(mesh.vertexCount*3*sizeof(float));
 
         int vCount = 0;
         int uvCount = 0;
-        while (vCount < mesh.vertexCount*3)
+        while (vCount < mesh.vertexCount*4)
         {
             // Calculate mesh vertex positions as Vector3
             Vector3 v0 = { mesh.vertices[vCount], mesh.vertices[vCount + 1], mesh.vertices[vCount + 2] };
@@ -2363,17 +2363,22 @@ static Mesh LoadOBJ(const char *fileName)
             // Calculate vertex tangent
             Vector3 tangent = Vector3Subtract(t1, t2);
             Vector3Scale(&tangent, r);
+            
+            // TODO: Calculate tangent 4th component
 
             // Apply calculated tangents data to mesh struct
             mesh.tangents[vCount + 0] = tangent.x;
             mesh.tangents[vCount + 1] = tangent.y;
             mesh.tangents[vCount + 2] = tangent.z;
-            mesh.tangents[vCount + 3] = tangent.x;
-            mesh.tangents[vCount + 4] = tangent.y;
-            mesh.tangents[vCount + 5] = tangent.z;
-            mesh.tangents[vCount + 6] = tangent.x;
-            mesh.tangents[vCount + 7] = tangent.y;
-            mesh.tangents[vCount + 8] = tangent.z;
+            mesh.tangents[vCount + 3] = 0.0f;
+            mesh.tangents[vCount + 4] = tangent.x;
+            mesh.tangents[vCount + 5] = tangent.y;
+            mesh.tangents[vCount + 6] = tangent.z;
+            mesh.tangents[vCount + 7] = 0.0f;
+            mesh.tangents[vCount + 8] = tangent.x;
+            mesh.tangents[vCount + 9] = tangent.y;
+            mesh.tangents[vCount + 10] = tangent.z;
+            mesh.tangents[vCount + 11] = 0.0f;
 
             // TODO: add binormals to mesh struct and assign buffers id and locations properly
             /* // Calculate vertex binormal
@@ -2392,7 +2397,7 @@ static Mesh LoadOBJ(const char *fileName)
             mesh.binormals[vCount + 8] = binormal.z; */
 
             // Update vertex position and texture coordinates counters
-            vCount += 9;
+            vCount += 12;
             uvCount += 6;
         }
     }

src/raylib.h

@@ -322,6 +322,14 @@ typedef struct Vector3 {
     float z;
 } Vector3;
 
+// Vector4 type
+typedef struct Vector4 {
+    float x;
+    float y;
+    float z;
+    float w;
+} Vector4;
+
 // Matrix type (OpenGL style 4x4 - right handed, column major)
 typedef struct Matrix {
     float m0, m4, m8, m12;
@@ -422,7 +430,7 @@ typedef struct Mesh {
     float *texcoords;       // Vertex texture coordinates (UV - 2 components per vertex) (shader-location = 1)
     float *texcoords2;      // Vertex second texture coordinates (useful for lightmaps) (shader-location = 5)
     float *normals;         // Vertex normals (XYZ - 3 components per vertex) (shader-location = 2)
-    float *tangents;        // Vertex tangents (XYZ - 3 components per vertex) (shader-location = 4)
+    float *tangents;        // Vertex tangents (XYZW - 4 components per vertex) (shader-location = 4)
     unsigned char *colors;  // Vertex colors (RGBA - 4 components per vertex) (shader-location = 3)
     unsigned short *indices;// Vertex indices (in case vertex data comes indexed)
 

src/rlgl.c

@@ -1782,14 +1782,14 @@ void rlLoadMesh(Mesh *mesh, bool dynamic)
     {
         glGenBuffers(1, &mesh->vboId[4]);
         glBindBuffer(GL_ARRAY_BUFFER, mesh->vboId[4]);
-        glBufferData(GL_ARRAY_BUFFER, sizeof(float)*3*mesh->vertexCount, mesh->tangents, drawHint);
-        glVertexAttribPointer(4, 3, GL_FLOAT, 0, 0, 0);
+        glBufferData(GL_ARRAY_BUFFER, sizeof(float)*4*mesh->vertexCount, mesh->tangents, drawHint);
+        glVertexAttribPointer(4, 4, GL_FLOAT, 0, 0, 0);
         glEnableVertexAttribArray(4);
     }
     else
     {
         // Default tangents vertex attribute
-        glVertexAttrib3f(4, 0.0f, 0.0f, 0.0f);
+        glVertexAttrib4f(4, 0.0f, 0.0f, 0.0f, 0.0f);
         glDisableVertexAttribArray(4);
     }
 
@@ -1804,7 +1804,7 @@ void rlLoadMesh(Mesh *mesh, bool dynamic)
     }
     else
     {
-        // Default tangents vertex attribute
+        // Default texcoord2 vertex attribute
         glVertexAttrib2f(5, 0.0f, 0.0f);
         glDisableVertexAttribArray(5);
     }
@@ -1868,8 +1868,8 @@ void rlUpdateMesh(Mesh mesh, int buffer, int numVertex)
         case 4:     // Update tangents (vertex tangents)
         {
             glBindBuffer(GL_ARRAY_BUFFER, mesh.vboId[4]);
-            if (numVertex >= mesh.vertexCount) glBufferData(GL_ARRAY_BUFFER, sizeof(float)*3*numVertex, mesh.tangents, GL_DYNAMIC_DRAW);
-            else glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(float)*3*numVertex, mesh.tangents);
+            if (numVertex >= mesh.vertexCount) glBufferData(GL_ARRAY_BUFFER, sizeof(float)*4*numVertex, mesh.tangents, GL_DYNAMIC_DRAW);
+            else glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(float)*4*numVertex, mesh.tangents);
         } break;
         case 5:     // Update texcoords2 (vertex second texture coordinates)
         {
@@ -2019,7 +2019,7 @@ void rlDrawMesh(Mesh mesh, Material material, Matrix transform)
         if (material.shader.locs[LOC_VERTEX_TANGENT] != -1)
         {
             glBindBuffer(GL_ARRAY_BUFFER, mesh.vboId[4]);
-            glVertexAttribPointer(material.shader.locs[LOC_VERTEX_TANGENT], 3, GL_FLOAT, 0, 0, 0);
+            glVertexAttribPointer(material.shader.locs[LOC_VERTEX_TANGENT], 4, GL_FLOAT, 0, 0, 0);
             glEnableVertexAttribArray(material.shader.locs[LOC_VERTEX_TANGENT]);
         }
 

src/rlgl.h

@@ -187,7 +187,7 @@ typedef unsigned char byte;
         float *texcoords;       // vertex texture coordinates (UV - 2 components per vertex) (shader-location = 1)
         float *texcoords2;      // vertex second texture coordinates (useful for lightmaps) (shader-location = 5)
         float *normals;         // vertex normals (XYZ - 3 components per vertex) (shader-location = 2)
-        float *tangents;        // vertex tangents (XYZ - 3 components per vertex) (shader-location = 4)
+        float *tangents;        // vertex tangents (XYZW - 4 components per vertex) (shader-location = 4)
         unsigned char *colors;  // vertex colors (RGBA - 4 components per vertex) (shader-location = 3)
         unsigned short *indices;// vertex indices (in case vertex data comes indexed)