/// <summary>
/// Draws this pass using the specified drawing context.
/// </summary>
public override void Draw(DrawingContext context, IList <IDrawableObject> drawables)
{
if (shadowCasterQuery == null)
{
shadowCasterQuery = context.CreateSpatialQuery <IDrawableObject>(drawable => drawable.CastShadow);
}
light.UpdateShadowFrustum(context, shadowCasterQuery);
shadowCasterQuery.FindAll(light.ShadowFrustum, shadowCasters);
Matrix oldView = context.matrices.view;
Matrix oldProjection = context.matrices.projection;
Begin();
// Leave the border pixels untouched so the shadow will not be stretched
// when using clamped sampling.
var viewport = context.graphics.Viewport;
context.graphics.Viewport = new Viewport(viewport.X + 1, viewport.Y + 1, viewport.Width - 2, viewport.Height - 2);
context.matrices.View = light.ShadowFrustum.Matrix;
context.matrices.Projection = Matrix.Identity;
context.graphics.SamplerStates[0] = SamplerState.PointClamp;
context.graphics.BlendState = BlendState.Opaque;
context.graphics.DepthStencilState = DepthStencilState.Default;
for (int i = 0; i < shadowCasters.Count; ++i)
{
var shadowCaster = shadowCasters[i];
if (!shadowCaster.OnAddedToView(context))
{
continue;
}
var material = shadowCaster.Material;
if (material == null)
{
material = depthMaterial;
}
else
{
material = material.GetMaterialByUsage(MaterialUsage.Depth);
}
if (material != null)
{
shadowCaster.Draw(context, material);
}
}
shadowCasters.Clear();
End(context);
context.matrices.View = oldView;
context.matrices.Projection = oldProjection;
}
