FiE-Game/Assets/Standard Assets/Effects/ImageEffects/Scripts/GlobalFog.cs
2023-07-25 00:52:50 +05:00

100 lines
4.2 KiB
C#

using System;
using UnityEngine;
namespace UnityStandardAssets.ImageEffects
{
[ExecuteInEditMode]
[RequireComponent (typeof(Camera))]
[AddComponentMenu ("Image Effects/Rendering/Global Fog")]
class GlobalFog : PostEffectsBase
{
[Tooltip("Apply distance-based fog?")]
public bool distanceFog = true;
[Tooltip("Exclude far plane pixels from distance-based fog? (Skybox or clear color)")]
public bool excludeFarPixels = true;
[Tooltip("Distance fog is based on radial distance from camera when checked")]
public bool useRadialDistance = false;
[Tooltip("Apply height-based fog?")]
public bool heightFog = true;
[Tooltip("Fog top Y coordinate")]
public float height = 1.0f;
[Range(0.001f,10.0f)]
public float heightDensity = 2.0f;
[Tooltip("Push fog away from the camera by this amount")]
public float startDistance = 0.0f;
public Shader fogShader = null;
private Material fogMaterial = null;
public override bool CheckResources ()
{
CheckSupport (true);
fogMaterial = CheckShaderAndCreateMaterial (fogShader, fogMaterial);
if (!isSupported)
ReportAutoDisable ();
return isSupported;
}
[ImageEffectOpaque]
void OnRenderImage(RenderTexture source, RenderTexture destination)
{
if (CheckResources() == false || (!distanceFog && !heightFog))
{
Graphics.Blit(source, destination);
return;
}
Camera cam = GetComponent<Camera>();
Transform camtr = cam.transform;
Vector3[] frustumCorners = new Vector3[4];
cam.CalculateFrustumCorners(new Rect(0, 0, 1, 1), cam.farClipPlane, cam.stereoActiveEye, frustumCorners);
var bottomLeft = camtr.TransformVector(frustumCorners[0]);
var topLeft = camtr.TransformVector(frustumCorners[1]);
var topRight = camtr.TransformVector(frustumCorners[2]);
var bottomRight = camtr.TransformVector(frustumCorners[3]);
Matrix4x4 frustumCornersArray = Matrix4x4.identity;
frustumCornersArray.SetRow(0, bottomLeft);
frustumCornersArray.SetRow(1, bottomRight);
frustumCornersArray.SetRow(2, topLeft);
frustumCornersArray.SetRow(3, topRight);
var camPos = camtr.position;
float FdotC = camPos.y - height;
float paramK = (FdotC <= 0.0f ? 1.0f : 0.0f);
float excludeDepth = (excludeFarPixels ? 1.0f : 2.0f);
fogMaterial.SetMatrix("_FrustumCornersWS", frustumCornersArray);
fogMaterial.SetVector("_CameraWS", camPos);
fogMaterial.SetVector("_HeightParams", new Vector4(height, FdotC, paramK, heightDensity * 0.5f));
fogMaterial.SetVector("_DistanceParams", new Vector4(-Mathf.Max(startDistance, 0.0f), excludeDepth, 0, 0));
var sceneMode = RenderSettings.fogMode;
var sceneDensity = RenderSettings.fogDensity;
var sceneStart = RenderSettings.fogStartDistance;
var sceneEnd = RenderSettings.fogEndDistance;
Vector4 sceneParams;
bool linear = (sceneMode == FogMode.Linear);
float diff = linear ? sceneEnd - sceneStart : 0.0f;
float invDiff = Mathf.Abs(diff) > 0.0001f ? 1.0f / diff : 0.0f;
sceneParams.x = sceneDensity * 1.2011224087f; // density / sqrt(ln(2)), used by Exp2 fog mode
sceneParams.y = sceneDensity * 1.4426950408f; // density / ln(2), used by Exp fog mode
sceneParams.z = linear ? -invDiff : 0.0f;
sceneParams.w = linear ? sceneEnd * invDiff : 0.0f;
fogMaterial.SetVector("_SceneFogParams", sceneParams);
fogMaterial.SetVector("_SceneFogMode", new Vector4((int)sceneMode, useRadialDistance ? 1 : 0, 0, 0));
int pass = 0;
if (distanceFog && heightFog)
pass = 0; // distance + height
else if (distanceFog)
pass = 1; // distance only
else
pass = 2; // height only
Graphics.Blit(source, destination, fogMaterial, pass);
}
}
}