CrowdControl/Assets/Top Down/Standard Assets/Image Effects (Pro Only)/GlowEffect.cs

using UnityEngine;

// Glow uses the alpha channel as a source of "extra brightness".
// All builtin Unity shaders output baseTexture.alpha * color.alpha, plus
// specularHighlight * specColor.alpha into that.
// Usually you'd want either to make base textures to have zero alpha; or
// set the color to have zero alpha (by default alpha is 0.5).
 
[ExecuteInEditMode]
[RequireComponent (typeof(Camera))]
[AddComponentMenu("Image Effects/Glow")]
public class GlowEffect : MonoBehaviour
{
	/// The brightness of the glow. Values larger than one give extra "boost".
	public float glowIntensity = 1.5f;
	
	/// Blur iterations - larger number means more blur.
	public int blurIterations = 3;
	
	/// Blur spread for each iteration. Lower values
	/// give better looking blur, but require more iterations to
	/// get large blurs. Value is usually between 0.5 and 1.0.
	public float blurSpread = 0.7f;
	
	/// Tint glow with this color. Alpha adds additional glow everywhere.
	public Color glowTint = new Color(1,1,1,0);
	
	
	// --------------------------------------------------------
	// The final composition shader:
	//   adds (glow color * glow alpha * amount) to the original image.
	// In the combiner glow amount can be only in 0..1 range; we apply extra
	// amount during the blurring phase.
	
    public Shader compositeShader;
    Material m_CompositeMaterial = null;
	protected Material compositeMaterial {
		get {
			if (m_CompositeMaterial == null) {
                m_CompositeMaterial = new Material(compositeShader);
				m_CompositeMaterial.hideFlags = HideFlags.HideAndDontSave;
			}
			return m_CompositeMaterial;
		} 
	}
	
	
	// --------------------------------------------------------
	// The blur iteration shader.
	// Basically it just takes 4 texture samples and averages them.
	// By applying it repeatedly and spreading out sample locations
	// we get a Gaussian blur approximation.
	// The alpha value in _Color would normally be 0.25 (to average 4 samples),
	// however if we have glow amount larger than 1 then we increase this.

    public Shader blurShader;
    Material m_BlurMaterial = null;
	protected Material blurMaterial {
		get {
			if (m_BlurMaterial == null) {
                m_BlurMaterial = new Material(blurShader);
                m_BlurMaterial.hideFlags = HideFlags.HideAndDontSave;
			}
			return m_BlurMaterial;
		} 
	}
	
	
	// --------------------------------------------------------
	// The image downsample shaders for each brightness mode.
	// It is in external assets as it's quite complex and uses Cg.
	public Shader downsampleShader;
	Material m_DownsampleMaterial = null;
	protected Material downsampleMaterial {
		get {
			if (m_DownsampleMaterial == null) {
				m_DownsampleMaterial = new Material( downsampleShader );
				m_DownsampleMaterial.hideFlags = HideFlags.HideAndDontSave;
			}
			return m_DownsampleMaterial;
		} 
	}
	
	
	// --------------------------------------------------------
	//  finally, the actual code
	
	protected void OnDisable()
	{
		if( m_CompositeMaterial ) {
			DestroyImmediate( m_CompositeMaterial );
		}
		if( m_BlurMaterial ) {
			DestroyImmediate( m_BlurMaterial );
		}
		if( m_DownsampleMaterial )
			DestroyImmediate( m_DownsampleMaterial );
	}
	
	protected void Start()
	{
		// Disable if we don't support image effects
		if (!SystemInfo.supportsImageEffects)
		{
			enabled = false;
			return;
		}
		
		// Disable the effect if no downsample shader is setup
		if( downsampleShader == null )
		{
			Debug.Log ("No downsample shader assigned! Disabling glow.");
			enabled = false;
		}
		// Disable if any of the shaders can't run on the users graphics card
		else
		{		
			if( !blurMaterial.shader.isSupported )
				enabled = false;
			if( !compositeMaterial.shader.isSupported )
				enabled = false;
			if( !downsampleMaterial.shader.isSupported )
				enabled = false;
		}
	}
	
	// Performs one blur iteration.
	public void FourTapCone (RenderTexture source, RenderTexture dest, int iteration)
	{
		float off = 0.5f + iteration*blurSpread;
		Graphics.BlitMultiTap (source, dest, blurMaterial,
            new