Baking vertex lighting - matching scale

Unity Engine
1

Hey guys, for an optimisation I am baking vertex lighting into a model.

I started with this http://www.unifycommunity.com/wiki/index.php?title=PixelLightMapper but had to modify it a lot. I am very close with directionals and point lights now.

However, I’m having a hard time matching lighting on non uniform scaled objects.

        for (int vertexIndex = 0; vertexIndex < sourceMesh.vertexCount; ++vertexIndex )
        {
            Vector3 worldPosition = sourceTransform.TransformPoint(sourceMesh.vertices[vertexIndex]);
            Vector3 worldNormal = sourceTransform.TransformPoint(sourceMesh.normals[vertexIndex] + sourceMesh.vertices[vertexIndex]) - worldPosition;

            worldNormal.Normalize();

            Color calculatedColor = Color.black;

            foreach (Light light in lights)
            {
                if (light.active)
                {
                    Transform lightTransform = light.transform;

                    //POINT LIGHT
                    if (light.type == LightType.Point)
                    {
                        Vector3 toLight = lightTransform.position - worldPosition;
                        float distanceToLight = toLight.magnitude;

                        toLight *= 1.0f / distanceToLight;

                        if (light.range > distanceToLight)
                        {
                            float angleMod = Mathf.Max(Vector3.Dot(worldNormal, toLight), 0.0f);
                            float r = Mathf.Clamp01((distanceToLight / light.range));
                            float attenuationMod = 1.0f / (1.0f + 25.0f * r * r);

                            calculatedColor += light.color * light.intensity * angleMod * attenuationMod;
                        }
                    }
                    else if (light.type == LightType.Directional)
                    {
                        float angleMod = Mathf.Max(Vector3.Dot(worldNormal, -lightTransform.forward), 0.0f);

                        calculatedColor += light.color * light.intensity * angleMod;
                    }
                }
            } //END foreach light

            calculatedColor *= tint;

            calculatedColor += emissive;

            m_colors[vertexIndex] = calculatedColor;

These are the offending lines

            Vector3 worldNormal = sourceTransform.TransformPoint(sourceMesh.normals[vertexIndex] + sourceMesh.vertices[vertexIndex]) - worldPosition;

            worldNormal.Normalize();

I have tried various combinations and so far failed. How does unity calculate the matrix applied to the normals?

Many thanks

Dan

2

Fixed

Matrix4x4 normalTransformMatrix = sourceTransform.localToWorldMatrix.inverse.transpose;