Added optional GPU skinning

src/raylib.h

@@ -352,8 +352,10 @@ typedef struct Mesh {
     // Animation vertex data
     float *animVertices;    // Animated vertex positions (after bones transformations)
     float *animNormals;     // Animated normals (after bones transformations)
-    unsigned char *boneIds; // Vertex bone ids, max 255 bone ids, up to 4 bones influence by vertex (skinning)
+    unsigned char *boneIds; // Vertex bone ids, max 255 bone ids, up to 4 bones influence by vertex (skinning) (shader-location = 6)
-    float *boneWeights;     // Vertex bone weight, up to 4 bones influence by vertex (skinning)
+    float *boneWeights;     // Vertex bone weight, up to 4 bones influence by vertex (skinning) (shader-location = 7)
+    Matrix *boneMatrices;   // Bones animated transformation matrices
+    int boneCount;          // Number of bones
 
     // OpenGL identifiers
     unsigned int vaoId;     // OpenGL Vertex Array Object id
@@ -771,11 +773,14 @@ typedef enum {
     SHADER_LOC_VERTEX_NORMAL,       // Shader location: vertex attribute: normal
     SHADER_LOC_VERTEX_TANGENT,      // Shader location: vertex attribute: tangent
     SHADER_LOC_VERTEX_COLOR,        // Shader location: vertex attribute: color
+    SHADER_LOC_VERTEX_BONEIDS,      // Shader location: vertex attribute: boneIds
+    SHADER_LOC_VERTEX_BONEWEIGHTS,  // Shader location: vertex attribute: boneWeights
     SHADER_LOC_MATRIX_MVP,          // Shader location: matrix uniform: model-view-projection
     SHADER_LOC_MATRIX_VIEW,         // Shader location: matrix uniform: view (camera transform)
     SHADER_LOC_MATRIX_PROJECTION,   // Shader location: matrix uniform: projection
     SHADER_LOC_MATRIX_MODEL,        // Shader location: matrix uniform: model (transform)
     SHADER_LOC_MATRIX_NORMAL,       // Shader location: matrix uniform: normal
+    SHADER_LOC_BONE_MATRICES,       // Shader location: array of matrices uniform: boneMatrices
     SHADER_LOC_VECTOR_VIEW,         // Shader location: vector uniform: view
     SHADER_LOC_COLOR_DIFFUSE,       // Shader location: vector uniform: diffuse color
     SHADER_LOC_COLOR_SPECULAR,      // Shader location: vector uniform: specular color
@@ -1590,6 +1595,7 @@ RLAPI void UpdateModelAnimation(Model model, ModelAnimation anim, int frame);
 RLAPI void UnloadModelAnimation(ModelAnimation anim);                                       // Unload animation data
 RLAPI void UnloadModelAnimations(ModelAnimation *animations, int animCount);                // Unload animation array data
 RLAPI bool IsModelAnimationValid(Model model, ModelAnimation anim);                         // Check model animation skeleton match
+RLAPI void UpdateModelAnimationBoneMatrices(Model model, ModelAnimation anim, int frame);   // Update model animation mesh bone matrices
 
 // Collision detection functions
 RLAPI bool CheckCollisionSpheres(Vector3 center1, float radius1, Vector3 center2, float radius2);   // Check collision between two spheres

src/rcore.c

@@ -1295,6 +1295,8 @@ Shader LoadShaderFromMemory(const char *vsCode, const char *fsCode)
         //          vertex color location       = 3
         //          vertex tangent location     = 4
         //          vertex texcoord2 location   = 5
+        //          vertex boneIds location     = 6
+        //          vertex boneWeights location = 7
 
         // NOTE: If any location is not found, loc point becomes -1
 
@@ -1310,6 +1312,8 @@ Shader LoadShaderFromMemory(const char *vsCode, const char *fsCode)
         shader.locs[SHADER_LOC_VERTEX_NORMAL] = rlGetLocationAttrib(shader.id, RL_DEFAULT_SHADER_ATTRIB_NAME_NORMAL);
         shader.locs[SHADER_LOC_VERTEX_TANGENT] = rlGetLocationAttrib(shader.id, RL_DEFAULT_SHADER_ATTRIB_NAME_TANGENT);
         shader.locs[SHADER_LOC_VERTEX_COLOR] = rlGetLocationAttrib(shader.id, RL_DEFAULT_SHADER_ATTRIB_NAME_COLOR);
+        shader.locs[SHADER_LOC_VERTEX_BONEIDS] = rlGetLocationAttrib(shader.id, RL_DEFAULT_SHADER_ATTRIB_NAME_BONEIDS);
+        shader.locs[SHADER_LOC_VERTEX_BONEWEIGHTS] = rlGetLocationAttrib(shader.id, RL_DEFAULT_SHADER_ATTRIB_NAME_BONEWEIGHTS);
 
         // Get handles to GLSL uniform locations (vertex shader)
         shader.locs[SHADER_LOC_MATRIX_MVP] = rlGetLocationUniform(shader.id, RL_DEFAULT_SHADER_UNIFORM_NAME_MVP);
@@ -1317,6 +1321,7 @@ Shader LoadShaderFromMemory(const char *vsCode, const char *fsCode)
         shader.locs[SHADER_LOC_MATRIX_PROJECTION] = rlGetLocationUniform(shader.id, RL_DEFAULT_SHADER_UNIFORM_NAME_PROJECTION);
         shader.locs[SHADER_LOC_MATRIX_MODEL] = rlGetLocationUniform(shader.id, RL_DEFAULT_SHADER_UNIFORM_NAME_MODEL);
         shader.locs[SHADER_LOC_MATRIX_NORMAL] = rlGetLocationUniform(shader.id, RL_DEFAULT_SHADER_UNIFORM_NAME_NORMAL);
+        shader.locs[SHADER_LOC_BONE_MATRICES] = rlGetLocationUniform(shader.id, RL_DEFAULT_SHADER_UNIFORM_NAME_BONE_MATRICES);
 
         // Get handles to GLSL uniform locations (fragment shader)
         shader.locs[SHADER_LOC_COLOR_DIFFUSE] = rlGetLocationUniform(shader.id, RL_DEFAULT_SHADER_UNIFORM_NAME_COLOR);

src/rlgl.h

@@ -68,12 +68,15 @@
 *       #define RL_DEFAULT_SHADER_ATTRIB_NAME_COLOR        "vertexColor"       // Bound by default to shader location: RL_DEFAULT_SHADER_ATTRIB_LOCATION_COLOR
 *       #define RL_DEFAULT_SHADER_ATTRIB_NAME_TANGENT      "vertexTangent"     // Bound by default to shader location: RL_DEFAULT_SHADER_ATTRIB_LOCATION_TANGENT
 *       #define RL_DEFAULT_SHADER_ATTRIB_NAME_TEXCOORD2    "vertexTexCoord2"   // Bound by default to shader location: RL_DEFAULT_SHADER_ATTRIB_LOCATION_TEXCOORD2
+*       #define RL_DEFAULT_SHADER_ATTRIB_NAME_BONEIDS      "vertexBoneIds"     // Bound by default to shader location: RL_DEFAULT_SHADER_ATTRIB_LOCATION_BONEIDS
+*       #define RL_DEFAULT_SHADER_ATTRIB_NAME_BONEWEIGHTS  "vertexBoneWeights" // Bound by default to shader location: RL_DEFAULT_SHADER_ATTRIB_LOCATION_BONEWEIGHTS
 *       #define RL_DEFAULT_SHADER_UNIFORM_NAME_MVP         "mvp"               // model-view-projection matrix
 *       #define RL_DEFAULT_SHADER_UNIFORM_NAME_VIEW        "matView"           // view matrix
 *       #define RL_DEFAULT_SHADER_UNIFORM_NAME_PROJECTION  "matProjection"     // projection matrix
 *       #define RL_DEFAULT_SHADER_UNIFORM_NAME_MODEL       "matModel"          // model matrix
 *       #define RL_DEFAULT_SHADER_UNIFORM_NAME_NORMAL      "matNormal"         // normal matrix (transpose(inverse(matModelView)))
 *       #define RL_DEFAULT_SHADER_UNIFORM_NAME_COLOR       "colDiffuse"        // color diffuse (base tint color, multiplied by texture color)
+*       #define RL_DEFAULT_SHADER_UNIFORM_NAME_BONE_MATRICES  "boneMatrices"   // bone matrices
 *       #define RL_DEFAULT_SHADER_SAMPLER2D_NAME_TEXTURE0  "texture0"          // texture0 (texture slot active 0)
 *       #define RL_DEFAULT_SHADER_SAMPLER2D_NAME_TEXTURE1  "texture1"          // texture1 (texture slot active 1)
 *       #define RL_DEFAULT_SHADER_SAMPLER2D_NAME_TEXTURE2  "texture2"          // texture2 (texture slot active 2)
@@ -324,22 +327,28 @@
 
 // Default shader vertex attribute locations
 #ifndef RL_DEFAULT_SHADER_ATTRIB_LOCATION_POSITION
-    #define RL_DEFAULT_SHADER_ATTRIB_LOCATION_POSITION  0
+    #define RL_DEFAULT_SHADER_ATTRIB_LOCATION_POSITION    0
 #endif
 #ifndef RL_DEFAULT_SHADER_ATTRIB_LOCATION_TEXCOORD
-    #define RL_DEFAULT_SHADER_ATTRIB_LOCATION_TEXCOORD  1
+    #define RL_DEFAULT_SHADER_ATTRIB_LOCATION_TEXCOORD    1
 #endif
 #ifndef RL_DEFAULT_SHADER_ATTRIB_LOCATION_NORMAL
-    #define RL_DEFAULT_SHADER_ATTRIB_LOCATION_NORMAL    2
+    #define RL_DEFAULT_SHADER_ATTRIB_LOCATION_NORMAL      2
 #endif
 #ifndef RL_DEFAULT_SHADER_ATTRIB_LOCATION_COLOR
-    #define RL_DEFAULT_SHADER_ATTRIB_LOCATION_COLOR     3
+    #define RL_DEFAULT_SHADER_ATTRIB_LOCATION_COLOR       3
 #endif
     #ifndef RL_DEFAULT_SHADER_ATTRIB_LOCATION_TANGENT
-#define RL_DEFAULT_SHADER_ATTRIB_LOCATION_TANGENT       4
+#define RL_DEFAULT_SHADER_ATTRIB_LOCATION_TANGENT         4
 #endif
 #ifndef RL_DEFAULT_SHADER_ATTRIB_LOCATION_TEXCOORD2
-    #define RL_DEFAULT_SHADER_ATTRIB_LOCATION_TEXCOORD2 5
+    #define RL_DEFAULT_SHADER_ATTRIB_LOCATION_TEXCOORD2   5
+#endif
+#ifndef RL_DEFAULT_SHADER_ATTRIB_LOCATION_BONEIDS
+    #define RL_DEFAULT_SHADER_ATTRIB_LOCATION_BONEIDS     6
+#endif
+#ifndef RL_DEFAULT_SHADER_ATTRIB_LOCATION_BONEWEIGHTS
+    #define RL_DEFAULT_SHADER_ATTRIB_LOCATION_BONEWEIGHTS 7
 #endif
 
 //----------------------------------------------------------------------------------
@@ -759,6 +768,7 @@ RLAPI int rlGetLocationUniform(unsigned int shaderId, const char *uniformName);
 RLAPI int rlGetLocationAttrib(unsigned int shaderId, const char *attribName);   // Get shader location attribute
 RLAPI void rlSetUniform(int locIndex, const void *value, int uniformType, int count); // Set shader value uniform
 RLAPI void rlSetUniformMatrix(int locIndex, Matrix mat);                        // Set shader value matrix
+RLAPI void rlSetUniformMatrices(int locIndex, const Matrix *mat, int count);    // Set shader value matrices
 RLAPI void rlSetUniformSampler(int locIndex, unsigned int textureId);           // Set shader value sampler
 RLAPI void rlSetShader(unsigned int id, int *locs);                             // Set shader currently active (id and locations)
 
@@ -977,6 +987,12 @@ RLAPI void rlLoadDrawQuad(void);     // Load and draw a quad
 #ifndef RL_DEFAULT_SHADER_ATTRIB_NAME_TEXCOORD2
     #define RL_DEFAULT_SHADER_ATTRIB_NAME_TEXCOORD2    "vertexTexCoord2"   // Bound by default to shader location: RL_DEFAULT_SHADER_ATTRIB_NAME_TEXCOORD2
 #endif
+#ifndef RL_DEFAULT_SHADER_ATTRIB_NAME_BONEIDS
+    #define RL_DEFAULT_SHADER_ATTRIB_NAME_BONEIDS      "vertexBoneIds"     // Bound by default to shader location: RL_DEFAULT_SHADER_ATTRIB_NAME_BONEIDS
+#endif
+#ifndef RL_DEFAULT_SHADER_ATTRIB_NAME_BONEWEIGHTS
+    #define RL_DEFAULT_SHADER_ATTRIB_NAME_BONEWEIGHTS  "vertexBoneWeights" // Bound by default to shader location: RL_DEFAULT_SHADER_ATTRIB_NAME_BONEWEIGHTS
+#endif
 
 #ifndef RL_DEFAULT_SHADER_UNIFORM_NAME_MVP
     #define RL_DEFAULT_SHADER_UNIFORM_NAME_MVP         "mvp"               // model-view-projection matrix
@@ -996,6 +1012,9 @@ RLAPI void rlLoadDrawQuad(void);     // Load and draw a quad
 #ifndef RL_DEFAULT_SHADER_UNIFORM_NAME_COLOR
     #define RL_DEFAULT_SHADER_UNIFORM_NAME_COLOR       "colDiffuse"        // color diffuse (base tint color, multiplied by texture color)
 #endif
+#ifndef RL_DEFAULT_SHADER_UNIFORM_NAME_BONE_MATRICES
+    #define RL_DEFAULT_SHADER_UNIFORM_NAME_BONE_MATRICES  "boneMatrices"   // bone matrices
+#endif
 #ifndef RL_DEFAULT_SHADER_SAMPLER2D_NAME_TEXTURE0
     #define RL_DEFAULT_SHADER_SAMPLER2D_NAME_TEXTURE0  "texture0"          // texture0 (texture slot active 0)
 #endif
@@ -4148,6 +4167,8 @@ unsigned int rlLoadShaderProgram(unsigned int vShaderId, unsigned int fShaderId)
     glBindAttribLocation(program, RL_DEFAULT_SHADER_ATTRIB_LOCATION_COLOR, RL_DEFAULT_SHADER_ATTRIB_NAME_COLOR);
     glBindAttribLocation(program, RL_DEFAULT_SHADER_ATTRIB_LOCATION_TANGENT, RL_DEFAULT_SHADER_ATTRIB_NAME_TANGENT);
     glBindAttribLocation(program, RL_DEFAULT_SHADER_ATTRIB_LOCATION_TEXCOORD2, RL_DEFAULT_SHADER_ATTRIB_NAME_TEXCOORD2);
+    glBindAttribLocation(program, RL_DEFAULT_SHADER_ATTRIB_LOCATION_BONEIDS, RL_DEFAULT_SHADER_ATTRIB_NAME_BONEIDS);
+    glBindAttribLocation(program, RL_DEFAULT_SHADER_ATTRIB_LOCATION_BONEWEIGHTS, RL_DEFAULT_SHADER_ATTRIB_NAME_BONEWEIGHTS);
 
     // NOTE: If some attrib name is no found on the shader, it locations becomes -1
 
@@ -4283,6 +4304,14 @@ void rlSetUniformMatrix(int locIndex, Matrix mat)
 #endif
 }
 
+// Set shader value uniform matrix
+void rlSetUniformMatrices(int locIndex, const Matrix *matrices, int count)
+{
+#if defined(GRAPHICS_API_OPENGL_33) || defined(GRAPHICS_API_OPENGL_ES2)
+    glUniformMatrix4fv(locIndex, count, true, (const float*)matrices);
+#endif
+}
+
 // Set shader value uniform sampler
 void rlSetUniformSampler(int locIndex, unsigned int textureId)
 {

src/rmodels.c

@@ -130,7 +130,7 @@
     #define MAX_MATERIAL_MAPS       12    // Maximum number of maps supported
 #endif
 #ifndef MAX_MESH_VERTEX_BUFFERS
-    #define MAX_MESH_VERTEX_BUFFERS  7    // Maximum vertex buffers (VBO) per mesh
+    #define MAX_MESH_VERTEX_BUFFERS  9    // Maximum vertex buffers (VBO) per mesh
 #endif
 
 //----------------------------------------------------------------------------------
@@ -1252,7 +1252,9 @@ void UploadMesh(Mesh *mesh, bool dynamic)
     mesh->vboId[3] = 0;     // Vertex buffer: colors
     mesh->vboId[4] = 0;     // Vertex buffer: tangents
     mesh->vboId[5] = 0;     // Vertex buffer: texcoords2
-    mesh->vboId[6] = 0;     // Vertex buffer: indices
+    mesh->vboId[6] = 0;     // Vertex buffer: boneIds
+    mesh->vboId[7] = 0;     // Vertex buffer: boneWeights
+    mesh->vboId[8] = 0;     // Vertex buffer: indices
 
 #if defined(GRAPHICS_API_OPENGL_33) || defined(GRAPHICS_API_OPENGL_ES2)
     mesh->vaoId = rlLoadVertexArray();
@@ -1338,10 +1340,42 @@ void UploadMesh(Mesh *mesh, bool dynamic)
         rlSetVertexAttributeDefault(RL_DEFAULT_SHADER_ATTRIB_LOCATION_TEXCOORD2, value, SHADER_ATTRIB_VEC2, 2);
         rlDisableVertexAttribute(RL_DEFAULT_SHADER_ATTRIB_LOCATION_TEXCOORD2);
     }
+    
+    if (mesh->boneIds != NULL)
+    {
+        // Enable vertex attribute: boneIds (shader-location = 6)
+        mesh->vboId[6] = rlLoadVertexBuffer(mesh->boneIds, mesh->vertexCount*4*sizeof(unsigned char), dynamic);
+        rlSetVertexAttribute(RL_DEFAULT_SHADER_ATTRIB_LOCATION_BONEIDS, 4, RL_UNSIGNED_BYTE, 0, 0, 0);
+        rlEnableVertexAttribute(RL_DEFAULT_SHADER_ATTRIB_LOCATION_BONEIDS);
+    }
+    else
+    {
+        // Default vertex attribute: boneIds
+        // WARNING: Default value provided to shader if location available
+        float value[4] = { 0.0f, 0.0f, 0.0f, 0.0f };
+        rlSetVertexAttributeDefault(RL_DEFAULT_SHADER_ATTRIB_LOCATION_BONEIDS, value, SHADER_ATTRIB_VEC4, 4);
+        rlDisableVertexAttribute(RL_DEFAULT_SHADER_ATTRIB_LOCATION_BONEIDS);
+    }
+    
+    if (mesh->boneWeights != NULL)
+    {
+        // Enable vertex attribute: texcoord2 (shader-location = 5)
+        mesh->vboId[7] = rlLoadVertexBuffer(mesh->boneWeights, mesh->vertexCount*4*sizeof(float), dynamic);
+        rlSetVertexAttribute(RL_DEFAULT_SHADER_ATTRIB_LOCATION_BONEWEIGHTS, 4, RL_FLOAT, 0, 0, 0);
+        rlEnableVertexAttribute(RL_DEFAULT_SHADER_ATTRIB_LOCATION_BONEWEIGHTS);
+    }
+    else
+    {
+        // Default vertex attribute: texcoord2
+        // WARNING: Default value provided to shader if location available
+        float value[4] = { 0.0f, 0.0f, 0.0f, 0.0f };
+        rlSetVertexAttributeDefault(RL_DEFAULT_SHADER_ATTRIB_LOCATION_BONEWEIGHTS, value, SHADER_ATTRIB_VEC4, 2);
+        rlDisableVertexAttribute(RL_DEFAULT_SHADER_ATTRIB_LOCATION_BONEWEIGHTS);
+    }
 
     if (mesh->indices != NULL)
     {
-        mesh->vboId[6] = rlLoadVertexBufferElement(mesh->indices, mesh->triangleCount*3*sizeof(unsigned short), dynamic);
+        mesh->vboId[8] = rlLoadVertexBufferElement(mesh->indices, mesh->triangleCount*3*sizeof(unsigned short), dynamic);
     }
 
     if (mesh->vaoId > 0) TRACELOG(LOG_INFO, "VAO: [ID %i] Mesh uploaded successfully to VRAM (GPU)", mesh->vaoId);
@@ -1451,6 +1485,13 @@ void DrawMesh(Mesh mesh, Material material, Matrix transform)
 
     // Upload model normal matrix (if locations available)
     if (material.shader.locs[SHADER_LOC_MATRIX_NORMAL] != -1) rlSetUniformMatrix(material.shader.locs[SHADER_LOC_MATRIX_NORMAL], MatrixTranspose(MatrixInvert(matModel)));
+    
+    // Upload Bone Transforms    
+    if (material.shader.locs[SHADER_LOC_BONE_MATRICES] != -1)
+    {
+        rlSetUniformMatrices(material.shader.locs[SHADER_LOC_BONE_MATRICES], mesh.boneMatrices, mesh.boneCount);
+    }
+
     //-----------------------------------------------------
 
     // Bind active texture maps (if available)
@@ -1529,8 +1570,34 @@ void DrawMesh(Mesh mesh, Material material, Matrix transform)
             rlSetVertexAttribute(material.shader.locs[SHADER_LOC_VERTEX_TEXCOORD02], 2, RL_FLOAT, 0, 0, 0);
             rlEnableVertexAttribute(material.shader.locs[SHADER_LOC_VERTEX_TEXCOORD02]);
         }
+        
+        // Bind mesh VBO data: vertex bone ids (shader-location = 6, if available)
+        if (material.shader.locs[SHADER_LOC_VERTEX_BONEIDS] != -1)
+        {
+            if (mesh.vboId[6] != 0)
+            {
+                rlEnableVertexBuffer(mesh.vboId[6]);
+                rlSetVertexAttribute(material.shader.locs[SHADER_LOC_VERTEX_BONEIDS], 4, RL_UNSIGNED_BYTE, 0, 0, 0);
+                rlEnableVertexAttribute(material.shader.locs[SHADER_LOC_VERTEX_BONEIDS]);
+            }
+            else
+            {
+                // Set default value for defined vertex attribute in shader but not provided by mesh
+                // WARNING: It could result in GPU undefined behaviour
+                float value[4] = { 0.0f, 0.0f, 0.0f, 0.0f };
+                rlSetVertexAttributeDefault(material.shader.locs[SHADER_LOC_VERTEX_BONEIDS], value, SHADER_ATTRIB_VEC4, 4);
+                rlDisableVertexAttribute(material.shader.locs[SHADER_LOC_VERTEX_BONEIDS]);
+            }
+        }
+        
+        if (material.shader.locs[SHADER_LOC_VERTEX_BONEWEIGHTS] != -1)
+        {
+            rlEnableVertexBuffer(mesh.vboId[7]);
+            rlSetVertexAttribute(material.shader.locs[SHADER_LOC_VERTEX_BONEWEIGHTS], 4, RL_FLOAT, 0, 0, 0);
+            rlEnableVertexAttribute(material.shader.locs[SHADER_LOC_VERTEX_BONEWEIGHTS]);
+        }
 
-        if (mesh.indices != NULL) rlEnableVertexBufferElement(mesh.vboId[6]);
+        if (mesh.indices != NULL) rlEnableVertexBufferElement(mesh.vboId[8]);
     }
 
     int eyeCount = 1;
@@ -1825,6 +1892,7 @@ void UnloadMesh(Mesh mesh)
     RL_FREE(mesh.animNormals);
     RL_FREE(mesh.boneWeights);
     RL_FREE(mesh.boneIds);
+    RL_FREE(mesh.boneMatrices);
 }
 
 // Export mesh data to file
@@ -2255,6 +2323,50 @@ void UpdateModelAnimation(Model model, ModelAnimation anim, int frame)
     }
 }
 
+void UpdateModelAnimationBoneMatrices(Model model, ModelAnimation anim, int frame)
+{
+    if ((anim.frameCount > 0) && (anim.bones != NULL) && (anim.framePoses != NULL))
+    {
+        if (frame >= anim.frameCount) frame = frame%anim.frameCount;    
+    
+        for (int i = 0; i < model.meshCount; i++)
+        {
+            if (model.meshes[i].boneMatrices)
+            {
+                assert(model.meshes[i].boneCount == anim.boneCount);
+              
+                for (int boneId = 0; boneId < model.meshes[i].boneCount; boneId++)
+                {
+                    Vector3 inTranslation = model.bindPose[boneId].translation;
+                    Quaternion inRotation = model.bindPose[boneId].rotation;
+                    Vector3 inScale = model.bindPose[boneId].scale;
+                    
+                    Vector3 outTranslation = anim.framePoses[frame][boneId].translation;
+                    Quaternion outRotation = anim.framePoses[frame][boneId].rotation;
+                    Vector3 outScale = anim.framePoses[frame][boneId].scale;
+
+                    Vector3 invTranslation = Vector3RotateByQuaternion(Vector3Negate(inTranslation), QuaternionInvert(inRotation));
+                    Quaternion invRotation = QuaternionInvert(inRotation);
+                    Vector3 invScale = Vector3Divide((Vector3){ 1.0f, 1.0f, 1.0f }, inScale);
+
+                    Vector3 boneTranslation = Vector3Add(
+                        Vector3RotateByQuaternion(Vector3Multiply(outScale, invTranslation),
+                        outRotation), outTranslation); 
+                    Quaternion boneRotation = QuaternionMultiply(outRotation, invRotation);
+                    Vector3 boneScale = Vector3Multiply(outScale, invScale);
+                    
+                    Matrix boneMatrix = MatrixMultiply(MatrixMultiply(
+                        QuaternionToMatrix(boneRotation),
+                        MatrixTranslate(boneTranslation.x, boneTranslation.y, boneTranslation.z)),
+                        MatrixScale(boneScale.x, boneScale.y, boneScale.z));
+                    
+                    model.meshes[i].boneMatrices[boneId] = boneMatrix;
+                }
+            }
+        }
+    }
+}
+
 // Unload animation array data
 void UnloadModelAnimations(ModelAnimation *animations, int animCount)
 {