using UnityEngine;

namespace UnityStandardAssets.ImageEffects
{
	[ExecuteInEditMode]
	[RequireComponent(typeof(Camera))]
	[AddComponentMenu("Image Effects/Blur/Blur (Optimized)")]
	public class BlurOptimized : PostEffectsBase
	{
		public enum BlurType
		{
			StandardGauss = 0,
			SgxGauss = 1
		}

		[Range(0f, 2f)]
		public int downsample = 1;

		[Range(0f, 10f)]
		public float blurSize = 3f;

		[Range(1f, 4f)]
		public int blurIterations = 2;

		public BlurType blurType;

		public Shader blurShader;

		private Material blurMaterial;

		public override bool CheckResources()
		{
			CheckSupport(needDepth: false);
			blurMaterial = CheckShaderAndCreateMaterial(blurShader, blurMaterial);
			if (!isSupported)
			{
				ReportAutoDisable();
			}
			return isSupported;
		}

		public void OnDisable()
		{
			if ((bool)blurMaterial)
			{
				DestroyImmediate(blurMaterial);
			}
		}

		public void OnRenderImage(RenderTexture source, RenderTexture destination)
		{
			if (!CheckResources())
			{
				Graphics.Blit(source, destination);
				return;
			}
			float num = 1f / (1f * (float)(1 << downsample));
			blurMaterial.SetVector("_Parameter", new Vector4(blurSize * num, (0f - blurSize) * num, 0f, 0f));
			source.filterMode = FilterMode.Bilinear;
			int width = source.width >> downsample;
			int height = source.height >> downsample;
			RenderTexture renderTexture = RenderTexture.GetTemporary(width, height, 0, source.format);
			renderTexture.filterMode = FilterMode.Bilinear;
			Graphics.Blit(source, renderTexture, blurMaterial, 0);
			int num2 = ((blurType != 0) ? 2 : 0);
			for (int i = 0; i < blurIterations; i++)
			{
				float num3 = (float)i * 1f;
				blurMaterial.SetVector("_Parameter", new Vector4(blurSize * num + num3, (0f - blurSize) * num - num3, 0f, 0f));
				RenderTexture temporary = RenderTexture.GetTemporary(width, height, 0, source.format);
				temporary.filterMode = FilterMode.Bilinear;
				Graphics.Blit(renderTexture, temporary, blurMaterial, 1 + num2);
				RenderTexture.ReleaseTemporary(renderTexture);
				renderTexture = temporary;
				temporary = RenderTexture.GetTemporary(width, height, 0, source.format);
				temporary.filterMode = FilterMode.Bilinear;
				Graphics.Blit(renderTexture, temporary, blurMaterial, 2 + num2);
				RenderTexture.ReleaseTemporary(renderTexture);
				renderTexture = temporary;
			}
			Graphics.Blit(renderTexture, destination);
			RenderTexture.ReleaseTemporary(renderTexture);
		}
	}
}