Skeletal animation implementation

Resources/Editor/Shaders/OutlineFallback.ovfx

@@ -1,7 +1,16 @@
+#pass OUTLINE_PASS
+#engine_feature SKINNING
+
 #shader vertex
 #version 450 core
 
 layout(location = 0) in vec3 geo_Pos;
+#if defined(SKINNING)
+layout(location = 5) in uvec4 geo_BoneIDs;
+layout(location = 6) in vec4 geo_BoneWeights;
+#endif
+
+#include ":Shaders/Common/Skinning.ovfxh"
 
 layout(std140) uniform EngineUBO
 {
@@ -14,7 +23,12 @@ layout(std140) uniform EngineUBO
 
 void main()
 {
-	gl_Position = ubo_Projection * ubo_View * ubo_Model * vec4(geo_Pos, 1.0);
+	mat4 skinningMatrix = mat4(1.0);
+#if defined(SKINNING)
+	skinningMatrix = ComputeSkinningMatrix(geo_BoneIDs, geo_BoneWeights);
+#endif
+
+	gl_Position = ubo_Projection * ubo_View * ubo_Model * skinningMatrix * vec4(geo_Pos, 1.0);
 }
 
 #shader fragment

Resources/Editor/Shaders/PickingFallback.ovfx

@@ -1,7 +1,14 @@
+#pass PICKING_PASS
+#engine_feature SKINNING
+
 #shader vertex
 #version 450 core
 
 layout (location = 0) in vec3 geo_Pos;
+#if defined(SKINNING)
+layout (location = 5) in uvec4 geo_BoneIDs;
+layout (location = 6) in vec4 geo_BoneWeights;
+#endif
 
 layout (std140) uniform EngineUBO
 {
@@ -12,9 +19,16 @@ layout (std140) uniform EngineUBO
     float   ubo_Time;
 };
 
+#include ":Shaders/Common/Skinning.ovfxh"
+
 void main()
 {
-    gl_Position = ubo_Projection * ubo_View * ubo_Model * vec4(geo_Pos, 1.0);
+    mat4 skinningMatrix = mat4(1.0);
+#if defined(SKINNING)
+    skinningMatrix = ComputeSkinningMatrix(geo_BoneIDs, geo_BoneWeights);
+#endif
+
+    gl_Position = ubo_Projection * ubo_View * ubo_Model * skinningMatrix * vec4(geo_Pos, 1.0);
 }
 
 #shader fragment

Resources/Engine/Shaders/Common/Buffers/SkinningSSBO.ovfxh

@@ -0,0 +1,4 @@
+layout(std430, binding = 1) buffer SkinningSSBO
+{
+    mat4 ssbo_Bones[];
+};

Resources/Engine/Shaders/Common/Skinning.ovfxh

@@ -0,0 +1,23 @@
+#include ":Shaders/Common/Buffers/SkinningSSBO.ovfxh"
+
+mat4 ComputeSkinningMatrix(uvec4 p_boneIDs, vec4 p_boneWeights)
+{
+    const int boneCount = ssbo_Bones.length();
+    mat4 skinning = mat4(0.0);
+    float totalWeight = 0.0;
+
+    for (int i = 0; i < 4; ++i)
+    {
+        float w = p_boneWeights[i];
+        if (w > 0.0 && int(p_boneIDs[i]) < boneCount)
+        {
+            skinning += ssbo_Bones[p_boneIDs[i]] * w;
+            totalWeight += w;
+        }
+    }
+
+    if (totalWeight <= 0.0) return mat4(1.0);
+
+    return skinning / totalWeight;
+}
+

Resources/Engine/Shaders/ShadowFallback.ovfx

@@ -1,13 +1,26 @@
+#pass SHADOW_PASS
+#engine_feature SKINNING
+
 #shader vertex
 #version 450 core
 
 layout (location = 0) in vec3 geo_Pos;
+#if defined(SKINNING)
+layout (location = 5) in uvec4 geo_BoneIDs;
+layout (location = 6) in vec4 geo_BoneWeights;
+#endif
 
 #include ":Shaders/Common/Buffers/EngineUBO.ovfxh"
+#include ":Shaders/Common/Skinning.ovfxh"
 
 void main()
 {
-    gl_Position = ubo_Projection * ubo_View * ubo_Model * vec4(geo_Pos, 1.0);
+    mat4 skinningMatrix = mat4(1.0);
+#if defined(SKINNING)
+    skinningMatrix = ComputeSkinningMatrix(geo_BoneIDs, geo_BoneWeights);
+#endif
+
+    gl_Position = ubo_Projection * ubo_View * ubo_Model * skinningMatrix * vec4(geo_Pos, 1.0);
 }
 
 #shader fragment

Resources/Engine/Shaders/Standard.ovfx

@@ -5,18 +5,24 @@
 #feature NORMAL_MAPPING
 #feature DISTANCE_FADE
 #feature SPECULAR_WORKFLOW
+#engine_feature SKINNING
 
 #shader vertex
 #version 450 core
 
 #include ":Shaders/Common/Buffers/EngineUBO.ovfxh"
+#include ":Shaders/Common/Skinning.ovfxh"
 #include ":Shaders/Common/Utils.ovfxh"
 
 layout (location = 0) in vec3 geo_Pos;
 layout (location = 1) in vec2 geo_TexCoords;
 layout (location = 2) in vec3 geo_Normal;
 layout (location = 3) in vec3 geo_Tangent;
 layout (location = 4) in vec3 geo_Bitangent;
+#if defined(SKINNING)
+layout (location = 5) in uvec4 geo_BoneIDs;
+layout (location = 6) in vec4 geo_BoneWeights;
+#endif
 
 out VS_OUT
 {
@@ -32,10 +38,17 @@ out VS_OUT
 
 void main()
 {
-    vs_out.FragPos = vec3(ubo_Model * vec4(geo_Pos, 1.0));
+    mat4 skinningMatrix = mat4(1.0);
+#if defined(SKINNING)
+    skinningMatrix = ComputeSkinningMatrix(geo_BoneIDs, geo_BoneWeights);
+#endif
+
+    const mat4 modelMatrix = ubo_Model * skinningMatrix;
+
+    vs_out.FragPos = vec3(modelMatrix * vec4(geo_Pos, 1.0));
     vs_out.TexCoords = geo_TexCoords;
-    vs_out.Normal = normalize(mat3(transpose(inverse(ubo_Model))) * geo_Normal);
-    vs_out.TBN = ConstructTBN(ubo_Model, geo_Normal, geo_Tangent, geo_Bitangent);
+    vs_out.Normal = normalize(mat3(transpose(inverse(modelMatrix))) * geo_Normal);
+    vs_out.TBN = ConstructTBN(modelMatrix, geo_Normal, geo_Tangent, geo_Bitangent);
 
 #if defined(PARALLAX_MAPPING)
     const mat3 TBNi = transpose(vs_out.TBN);

Resources/Engine/Shaders/Unlit.ovfx

@@ -1,15 +1,21 @@
 #pass SHADOW_PASS
 
 #feature ALPHA_CLIPPING
+#engine_feature SKINNING
 
 #shader vertex
 #version 450 core
 
 #include ":Shaders/Common/Buffers/EngineUBO.ovfxh"
+#include ":Shaders/Common/Skinning.ovfxh"
 #include ":Shaders/Common/Utils.ovfxh"
 
 layout (location = 0) in vec3 geo_Pos;
 layout (location = 1) in vec2 geo_TexCoords;
+#if defined(SKINNING)
+layout (location = 5) in uvec4 geo_BoneIDs;
+layout (location = 6) in vec4 geo_BoneWeights;
+#endif
 
 out VS_OUT
 {
@@ -19,7 +25,14 @@ out VS_OUT
 
 void main()
 {
-    vs_out.FragPos = vec3(ubo_Model * vec4(geo_Pos, 1.0));
+    mat4 skinningMatrix = mat4(1.0);
+#if defined(SKINNING)
+    skinningMatrix = ComputeSkinningMatrix(geo_BoneIDs, geo_BoneWeights);
+#endif
+
+    const mat4 modelMatrix = ubo_Model * skinningMatrix;
+
+    vs_out.FragPos = vec3(modelMatrix * vec4(geo_Pos, 1.0));
     vs_out.TexCoords = geo_TexCoords;
 
     gl_Position = ubo_Projection * ubo_View * vec4(vs_out.FragPos, 1.0);