/// <summary>
/// Renders a light.
/// </summary>
/// <param name="light">The light.</param>
void IRenderer.Render(Light light)
{
if (light == null)
{
throw new ArgumentNullException(nameof(light));
}
if (this.Phase == Phase.Lights)
{
this.lightShader.Use(light);
if (light.Radius > 0)
{
var radius = light.Radius * 1.1f; // <- Grow the sphere slightly so that it fully encloses the light radius.
const int Stacks = 8;
const int Slices = 8;
this.vertexBuffer.BeginTriangleStrip(Stacks * (Slices + 1) * 2);
for (var stack = 0; stack < Stacks; stack++)
{
for (var slice = 0; slice <= Slices; slice++)
{
for (var i = 0; i < 2; i++)
{
var s = slice / (float)Slices;
var t = (stack + i) / (float)Stacks;
var sa = s * Math.PI * 2;
var ta = (t * Math.PI) - (Math.PI / 2);
var nx = (float)Math.Cos(sa) * (float)Math.Cos(ta);
var ny = (float)Math.Sin(sa) * (float)Math.Cos(ta);
var nz = (float)Math.Sin(ta);
this.vertexBuffer.Vertex(
light.Position.X + nx * radius,
light.Position.Y + ny * radius,
light.Position.Z + nz * radius);
}
}
}
this.vertexBuffer.End().Draw();
}
else
{
this.vertexBuffer.FullSceneQuad().Draw();
}
}
}
/// <summary>
/// Renders the scene.
/// </summary>
/// <param name="scene">The scene object.</param>
/// <param name="primaryLight">The primary light. Only the primary light casts shadows.</param>
public void Render(IScene scene, Light primaryLight)
{
if (scene == null)
{
throw new ArgumentNullException(nameof(scene));
}
// Phase 1: Geometry
{
this.Phase = Phase.Geometry;
GPU.Draw(ColorTarget, NormalTarget, PositionTarget, CompositionTarget);
GPU.Use(Cull.Back, Depth.Test | Depth.Write, Stencil.None, Blend.None);
GPU.Clear(null);
scene.Render(this);
}
// Phase 2: Shadows
if (primaryLight != null && primaryLight.Intensity > 0)
{
this.Phase = Phase.Shadows;
this.shadowShader.Use(primaryLight);
GPU.Draw(TargetBuffer.None);
GPU.Use(Cull.None, Depth.Test | Depth.Clamp | Depth.Offset, Stencil.Shadows, Blend.None);
scene.Render(this);
}
// Phase 3: Lights
{
this.Phase = Phase.Lights;
this.lightShader.Use()
.SetUniform("ColorBuffer", this.ColorBuffer)
.SetUniform("NormalBuffer", this.NormalBuffer)
.SetUniform("PositionBuffer", this.PositionBuffer)
.SetUniform("BufferSize", this.Width, this.Height);
GPU.Draw(CompositionTarget);
if (primaryLight != null && primaryLight.Intensity > 0)
{
GPU.Use(Cull.Back, Depth.TestReversed, Stencil.Light, Blend.Additive);
GPU.Transform(Matrix4x4.Identity);
(this as IRenderer).Render(primaryLight);
}
GPU.Use(Cull.Back, Depth.TestReversed, Stencil.None, Blend.Additive);
scene.Render(this);
}
// Phase 4: Effects
{
this.Phase = Phase.Effects;
GPU.Use(Cull.None, Depth.Test, Stencil.None, Blend.Additive);
scene.Render(this);
}
this.Phase = 0;
}
