Function applyAlphaFadeToLowerPart

src/content/Sky.cpp:495–519

* Sets the alpha-values of the lowest vertices in the mesh to do some fading. * * Gothic does this after loading the mesh. A better way would have been to simply bake this into the mesh... */

 * Gothic does this after loading the mesh. A better way would have been to simply bake this into the mesh...
 */
static void applyAlphaFadeToLowerPart(ZenLoad::PackedMesh& mesh)
{
    float lowestVertex = mesh.bbox[0].y;
    float highestVertex = mesh.bbox[1].y;
    float heightTotal = highestVertex - lowestVertex;

    const float heightTotalInv = 1.0f / heightTotal;

    for(ZenLoad::WorldVertex& vx : mesh.vertices)
    {
        if(vx.Position.y > 0)
        {
            vx.Color = 0xFFFFFFFF;
        }
        else
        {
            float vertexHeightRatio = Math::clamp(1.0f - (vx.Position.y - lowestVertex) * heightTotalInv, 0.0f, 1.0f);

            const float alpha = 1.0f - Math::sinusSlowEnd(vertexHeightRatio);
            Math::float4 color = Math::float4(1.0f, 1.0f, 1.0f, alpha);

            vx.Color = color.toRGBA8();
        }
    }
}


/**