/// <summary>
/// Lazily computes derived parameter values immediately before applying the effect.
/// </summary>
protected override void OnApply()
{
// Recompute the world+view+projection matrix or fog vector?
dirtyFlags = BlEffectHelpers.SetWorldViewProjAndFog(dirtyFlags, ref world, ref view, ref projection, ref worldView, fogEnabled, fogStart, fogEnd, worldViewProjParam, fogVectorParam);
// Recompute the diffuse/emissive/alpha material color parameters?
if ((dirtyFlags & BlEffectDirtyFlags.MaterialColor) != 0)
{
BlEffectHelpers.SetMaterialColor(lightingEnabled, alpha, ref diffuseColor, ref emissiveColor, ref ambientLightColor, diffuseColorParam, emissiveColorParam);
dirtyFlags &= ~BlEffectDirtyFlags.MaterialColor;
}
if (lightingEnabled)
{
// Recompute the world inverse transpose and eye position?
dirtyFlags = BlEffectHelpers.SetLightingMatrices(dirtyFlags, ref world, ref view, worldParam, worldInverseTransposeParam, eyePositionParam);
// Check if we can use the only-bother-with-the-first-light shader optimization.
bool newOneLight = !light1.Enabled && !light2.Enabled;
if (oneLight != newOneLight)
{
oneLight = newOneLight;
dirtyFlags |= BlEffectDirtyFlags.ShaderIndex;
}
}
// Recompute the shader index?
if ((dirtyFlags & BlEffectDirtyFlags.ShaderIndex) != 0)
{
int shaderIndex = 0;
if (!fogEnabled)
{
shaderIndex += 1;
}
if (vertexColorEnabled)
{
shaderIndex += 2;
}
if (textureEnabled)
{
shaderIndex += 4;
}
if (lightingEnabled)
{
if (preferPerPixelLighting)
{
shaderIndex += 24;
}
else if (oneLight)
{
shaderIndex += 16;
}
else
{
shaderIndex += 8;
}
}
dirtyFlags &= ~BlEffectDirtyFlags.ShaderIndex;
CurrentTechnique = Techniques[shaderIndex];
}
}
/// <inheritdoc/>
public void EnableDefaultLighting()
{
LightingEnabled = true;
AmbientLightColor = BlEffectHelpers.EnableDefaultLighting(light0, light1, light2);
}