ADD: Normal mapping

shaders/mesh.vert

@@ -9,6 +9,7 @@ layout (location = 0) out vec3 outNormal;
 layout (location = 1) out vec3 outColor;
 layout (location = 2) out vec2 outUV;
 layout (location = 3) out vec3 outWorldPos;
+layout (location = 4) out vec4 outTangent; // xyz: world tangent, w: sign
 
 struct Vertex {
 
@@ -17,6 +18,7 @@ struct Vertex {
     vec3 normal;
     float uv_y;
     vec4 color;
+    vec4 tangent;
 };
 
 layout(buffer_reference, std430) readonly buffer VertexBuffer{
@@ -38,6 +40,8 @@ void main()
     gl_Position = sceneData.viewproj * worldPos;
 
     outNormal = (PushConstants.render_matrix * vec4(v.normal, 0.f)).xyz;
+    vec3 worldTangent = (PushConstants.render_matrix * vec4(v.tangent.xyz, 0.f)).xyz;
+    outTangent = vec4(normalize(worldTangent), v.tangent.w);
     // Pass pure vertex color; apply baseColorFactor only in fragment
     outColor = v.color.xyz;
     outUV.x = v.uv_x;