using UnityEngine;

namespace UnityStandardAssets.ImageEffects
{
	[ExecuteInEditMode]
	[RequireComponent(typeof(Camera))]
	[AddComponentMenu("Image Effects/Color Adjustments/Contrast Enhance (Unsharp Mask)")]
	public class ContrastEnhance : PostEffectsBase
	{
		[Range(0f, 1f)]
		public float intensity = 0.5f;

		[Range(0f, 0.999f)]
		public float threshold;

		private Material separableBlurMaterial;

		private Material contrastCompositeMaterial;

		[Range(0f, 1f)]
		public float blurSpread = 1f;

		public Shader separableBlurShader;

		public Shader contrastCompositeShader;

		public override bool CheckResources()
		{
			CheckSupport(false);
			contrastCompositeMaterial = CheckShaderAndCreateMaterial(contrastCompositeShader, contrastCompositeMaterial);
			separableBlurMaterial = CheckShaderAndCreateMaterial(separableBlurShader, separableBlurMaterial);
			if (!isSupported)
			{
				ReportAutoDisable();
			}
			return isSupported;
		}

		private void OnRenderImage(RenderTexture source, RenderTexture destination)
		{
			if (!CheckResources())
			{
				Graphics.Blit(source, destination);
				return;
			}
			int width = source.width;
			int height = source.height;
			RenderTexture temporary = RenderTexture.GetTemporary(width / 2, height / 2, 0);
			Graphics.Blit(source, temporary);
			RenderTexture temporary2 = RenderTexture.GetTemporary(width / 4, height / 4, 0);
			Graphics.Blit(temporary, temporary2);
			RenderTexture.ReleaseTemporary(temporary);
			separableBlurMaterial.SetVector("offsets", new Vector4(0f, blurSpread * 1f / (float)temporary2.height, 0f, 0f));
			RenderTexture temporary3 = RenderTexture.GetTemporary(width / 4, height / 4, 0);
			Graphics.Blit(temporary2, temporary3, separableBlurMaterial);
			RenderTexture.ReleaseTemporary(temporary2);
			separableBlurMaterial.SetVector("offsets", new Vector4(blurSpread * 1f / (float)temporary2.width, 0f, 0f, 0f));
			temporary2 = RenderTexture.GetTemporary(width / 4, height / 4, 0);
			Graphics.Blit(temporary3, temporary2, separableBlurMaterial);
			RenderTexture.ReleaseTemporary(temporary3);
			contrastCompositeMaterial.SetTexture("_MainTexBlurred", temporary2);
			contrastCompositeMaterial.SetFloat("intensity", intensity);
			contrastCompositeMaterial.SetFloat("threshold", threshold);
			Graphics.Blit(source, destination, contrastCompositeMaterial);
			RenderTexture.ReleaseTemporary(temporary2);
		}
	}
}