lightshafts

using UnityEngine;
using System.Collections;

using System;

[ExecuteInEditMode]
[RequireComponent(typeof(Light))]
[RequireComponent(typeof(LightShaftsOptim))]
public partial class LightShafts : MonoBehaviour
{
    public void Start()
    {
        CheckMinRequirements();
        // HACK (Event[0]): Get camera on player
        if(Player.Instance != null && Player.Instance.head != null) {
            m_Cameras = new Camera[]{ Player.Instance.head.GetComponentInChildren<Camera>() };
        } else {
            m_Cameras = new Camera[]{ Camera.main };
        }

        UpdateCameraDepthMode();
    }

    void UpdateShadowmap()
    {
        if (m_ShadowmapMode == LightShaftsShadowmapMode.Static && !m_ShadowmapDirty)
            return;

        InitShadowmap();

        if (m_ShadowmapCamera == null)
        {
            GameObject go = new GameObject("Depth Camera");
            go.AddComponent(typeof(Camera));
            m_ShadowmapCamera = go.GetComponent<Camera>();
            go.hideFlags = HideFlags.HideAndDontSave;
            m_ShadowmapCamera.enabled = false;
            m_ShadowmapCamera.clearFlags = CameraClearFlags.SolidColor;
        }
        Transform cam = m_ShadowmapCamera.transform;
        cam.position = transform.position;
        cam.rotation = transform.rotation;

        if (directional)
        {
            m_ShadowmapCamera.orthographic = true;
            m_ShadowmapCamera.nearClipPlane = 0;
            m_ShadowmapCamera.farClipPlane = m_Size.z;
            m_ShadowmapCamera.orthographicSize = m_Size.y * 0.5f;
            m_ShadowmapCamera.aspect = m_Size.x / m_Size.y;
        }
        else
        {
            m_ShadowmapCamera.orthographic = false;
            m_ShadowmapCamera.nearClipPlane = m_SpotNear * m_Light.range;
            m_ShadowmapCamera.farClipPlane = m_SpotFar * m_Light.range;
            m_ShadowmapCamera.fieldOfView = m_Light.spotAngle;
            m_ShadowmapCamera.aspect = 1.0f;
        }
        m_ShadowmapCamera.renderingPath = RenderingPath.Forward;
        m_ShadowmapCamera.targetTexture = m_Shadowmap;
        m_ShadowmapCamera.cullingMask = m_CullingMask;
        m_ShadowmapCamera.backgroundColor = Color.white;

        m_ShadowmapCamera.RenderWithShader(m_DepthShader, "RenderType");

        if (m_Colored)
        {
            m_ShadowmapCamera.targetTexture = m_ColorFilter;
            m_ShadowmapCamera.cullingMask = m_ColorFilterMask;
            m_ShadowmapCamera.backgroundColor = new Color(m_ColorBalance, m_ColorBalance, m_ColorBalance);
            m_ShadowmapCamera.RenderWithShader(m_ColorFilterShader, "");
        }

        m_ShadowmapDirty = false;
    }

    void RenderCoords(int width, int height, Vector4 lightPos)
    {
        SetFrustumRays(m_CoordMaterial);

        RenderBuffer[] buffers = {m_CoordEpi.colorBuffer, m_DepthEpi.colorBuffer};
        Graphics.SetRenderTarget(buffers, m_DepthEpi.depthBuffer);
        m_CoordMaterial.SetVector("_LightPos", lightPos);
        m_CoordMaterial.SetVector("_CoordTexDim", new Vector4(m_CoordEpi.width, m_CoordEpi.height, 1.0f / m_CoordEpi.width, 1.0f / m_CoordEpi.height));
        m_CoordMaterial.SetVector("_ScreenTexDim", new Vector4(width, height, 1.0f / width, 1.0f / height));
        m_CoordMaterial.SetPass(0);
        RenderQuad();
    }

    void RenderInterpolationTexture(Vector4 lightPos)
    {
        Graphics.SetRenderTarget(m_InterpolationEpi.colorBuffer, m_RaymarchedLightEpi.depthBuffer);
        if (!m_DX11Support && (Application.platform == RuntimePlatform.WindowsEditor || Application.platform == RuntimePlatform.WindowsPlayer || Application.platform == RuntimePlatform.WindowsWebPlayer))
        {
            // Looks like in dx9 stencil is not cleared properly with GL.Clear()
            // Edit: fixed in 4.5, so this hack can be removed
            m_DepthBreaksMaterial.SetPass(1);
            RenderQuad();
        }
        else
        {
            GL.Clear(true, true, new Color(0, 0, 0, 1));
        }
        m_DepthBreaksMaterial.SetFloat("_InterpolationStep", m_InterpolationStep);
        m_DepthBreaksMaterial.SetFloat("_DepthThreshold", GetDepthThresholdAdjusted());
        m_DepthBreaksMaterial.SetTexture("_DepthEpi", m_DepthEpi);
        m_DepthBreaksMaterial.SetVector("_DepthEpiTexDim", new Vector4(m_DepthEpi.width, m_DepthEpi.height, 1.0f / m_DepthEpi.width, 1.0f / m_DepthEpi.height));
        m_DepthBreaksMaterial.SetPass(0);
        RenderQuadSections(lightPos);
    }

    void InterpolateAlongRays(Vector4 lightPos)
    {
        Graphics.SetRenderTarget(m_InterpolateAlongRaysEpi);
        m_InterpolateAlongRaysMaterial.SetFloat("_InterpolationStep", m_InterpolationStep);
        m_InterpolateAlongRaysMaterial.SetTexture("_InterpolationEpi", m_InterpolationEpi);
        m_InterpolateAlongRaysMaterial.SetTexture("_RaymarchedLightEpi", m_RaymarchedLightEpi);
        m_InterpolateAlongRaysMaterial.SetVector("_RaymarchedLightEpiTexDim", new Vector4(m_RaymarchedLightEpi.width, m_RaymarchedLightEpi.height, 1.0f / m_RaymarchedLightEpi.width, 1.0f / m_RaymarchedLightEpi.height));
        m_InterpolateAlongRaysMaterial.SetPass(0);
        RenderQuadSections(lightPos);
    }

    void RenderSamplePositions(int width, int height, Vector4 lightPos)
    {
        InitRenderTexture (ref m_SamplePositions, width, height, 0, RenderTextureFormat.ARGB32, false);
        // Unfortunately can't be a temporary RT if we want random write
        m_SamplePositions.enableRandomWrite = true;
        m_SamplePositions.filterMode = FilterMode.Point;

        Graphics.SetRenderTarget (m_SamplePositions);
        GL.Clear (false, true, new Color(0,0,0,1));

        Graphics.ClearRandomWriteTargets();
        Graphics.SetRandomWriteTarget(1, m_SamplePositions);

        //We need a render target with m_Coord dimensions, but reading and writing
        //to the same target produces wrong read results, so using a dummy.
        Graphics.SetRenderTarget(m_RaymarchedLightEpi);

        m_SamplePositionsMaterial.SetVector("_OutputTexDim", new Vector4(width-1, height-1, 0, 0));
        m_SamplePositionsMaterial.SetVector("_CoordTexDim", new Vector4(m_CoordEpi.width, m_CoordEpi.height, 0, 0));
        m_SamplePositionsMaterial.SetTexture("_Coord", m_CoordEpi);
        m_SamplePositionsMaterial.SetTexture("_InterpolationEpi", m_InterpolationEpi);

        if (m_ShowInterpolatedSamples)
        {
            m_SamplePositionsMaterial.SetFloat("_SampleType", 1);
            m_SamplePositionsMaterial.SetVector("_Color", new Vector4(0.4f, 0.4f, 0, 0));
            m_SamplePositionsMaterial.SetPass(0);
            RenderQuad();
        }

        m_SamplePositionsMaterial.SetFloat("_SampleType", 0);
        m_SamplePositionsMaterial.SetVector("_Color", new Vector4(1, 0, 0, 0));
        m_SamplePositionsMaterial.SetPass(0);
        RenderQuadSections(lightPos);

        Graphics.ClearRandomWriteTargets();
    }

    void ShowSamples(int width, int height, Vector4 lightPos)
    {
        bool showSamples = m_ShowSamples && m_DX11Support && m_SamplePositionsShaderCompiles;
        SetKeyword(showSamples, "SHOW_SAMPLES_ON", "SHOW_SAMPLES_OFF");
        if (showSamples)
            RenderSamplePositions(width, height, lightPos);

        m_FinalInterpolationMaterial.SetFloat("_ShowSamplesBackgroundFade", m_ShowSamplesBackgroundFade);
    }

    void Raymarch(int width, int height, Vector4 lightPos)
    {
        SetFrustumRays(m_RaymarchMaterial);

        int shadowmapWidth = m_Shadowmap.width;
        int shadowmapHeight = m_Shadowmap.height;

        Graphics.SetRenderTarget(m_RaymarchedLightEpi.colorBuffer, m_RaymarchedLightEpi.depthBuffer);
        GL.Clear(false, true, new Color(0, 0, 0, 1));
        m_RaymarchMaterial.SetTexture("_Coord", m_CoordEpi);
        m_RaymarchMaterial.SetTexture("_InterpolationEpi", m_InterpolationEpi);
        m_RaymarchMaterial.SetTexture("_Shadowmap", m_Shadowmap);
        float brightness = m_Colored ? m_BrightnessColored/m_ColorBalance : m_Brightness;
        brightness *= m_Light.intensity;
        m_RaymarchMaterial.SetFloat("_Brightness", brightness);
        m_RaymarchMaterial.SetFloat("_Extinction", -m_Extinction);
        m_RaymarchMaterial.SetVector("_ShadowmapDim", new Vector4(shadowmapWidth, shadowmapHeight, 1.0f / shadowmapWidth, 1.0f / shadowmapHeight));
        m_RaymarchMaterial.SetVector("_ScreenTexDim", new Vector4(width, height, 1.0f / width, 1.0f / height));
        m_RaymarchMaterial.SetVector("_LightColor", m_Light.color.linear);
        m_RaymarchMaterial.SetFloat("_MinDistFromCamera", m_MinDistFromCamera);
        SetKeyword(m_Colored, "COLORED_ON", "COLORED_OFF");
        m_RaymarchMaterial.SetTexture("_ColorFilter", m_ColorFilter);
        SetKeyword(m_AttenuationCurveOn, "ATTENUATION_CURVE_ON", "ATTENUATION_CURVE_OFF");
        m_RaymarchMaterial.SetTexture("_AttenuationCurveTex", m_AttenuationCurveTex);
        Texture cookie = m_Light.cookie;
        SetKeyword(cookie != null, "COOKIE_TEX_ON", "COOKIE_TEX_OFF");
        if (cookie != null)
            m_RaymarchMaterial.SetTexture("_Cookie", cookie);
        m_RaymarchMaterial.SetPass(0);

        RenderQuadSections(lightPos);
    }

    public void OnRenderObject ()
    {
        m_CurrentCamera = Camera.current;
        if (!m_MinRequirements || !CheckCamera() || !IsVisible())
            return;

        // Prepare
        RenderBuffer depthBuffer = Graphics.activeDepthBuffer;
        RenderBuffer colorBuffer = Graphics.activeColorBuffer;
        InitResources();
        Vector4 lightPos = GetLightViewportPos();
        bool lightOnScreen = lightPos.x >= -1 && lightPos.x <= 1 && lightPos.y >= -1 && lightPos.y <= 1;
        SetKeyword(lightOnScreen, "LIGHT_ON_SCREEN", "LIGHT_OFF_SCREEN");
        int width = Screen.width;
        int height = Screen.height;

        // Render the buffers, raymarch, interpolate along rays
        UpdateShadowmap();
        SetKeyword(directional, "DIRECTIONAL_SHAFTS", "SPOT_SHAFTS");
        RenderCoords(width, height, lightPos);
        RenderInterpolationTexture(lightPos);
        Raymarch(width, height, lightPos);
        InterpolateAlongRays(lightPos);

        ShowSamples(width, height, lightPos);

        // Final interpolation and blending onto the screen
        SetFrustumRays(m_FinalInterpolationMaterial);
        m_FinalInterpolationMaterial.SetTexture("_InterpolationEpi", m_InterpolationEpi);
        m_FinalInterpolationMaterial.SetTexture("_DepthEpi", m_DepthEpi);
        m_FinalInterpolationMaterial.SetTexture("_Shadowmap", m_Shadowmap);
        m_FinalInterpolationMaterial.SetTexture("_Coord", m_CoordEpi);
        m_FinalInterpolationMaterial.SetTexture("_SamplePositions", m_SamplePositions);
        m_FinalInterpolationMaterial.SetTexture("_RaymarchedLight", m_InterpolateAlongRaysEpi);
        m_FinalInterpolationMaterial.SetVector("_CoordTexDim", new Vector4(m_CoordEpi.width, m_CoordEpi.height, 1.0f / m_CoordEpi.width, 1.0f / m_CoordEpi.height));
        m_FinalInterpolationMaterial.SetVector("_ScreenTexDim", new Vector4(width, height, 1.0f / width, 1.0f / height));
        m_FinalInterpolationMaterial.SetVector("_LightPos", lightPos);
        m_FinalInterpolationMaterial.SetFloat("_DepthThreshold", GetDepthThresholdAdjusted());
        bool renderAsQuad = directional || IntersectsNearPlane();
        m_FinalInterpolationMaterial.SetFloat("_ZTest", (float)(renderAsQuad ? UnityEngine.Rendering.CompareFunction.Always : UnityEngine.Rendering.CompareFunction.Less));
        SetKeyword(renderAsQuad, "QUAD_SHAFTS", "FRUSTUM_SHAFTS");

        Graphics.SetRenderTarget(colorBuffer, depthBuffer);
        m_FinalInterpolationMaterial.SetPass(0);
        if (renderAsQuad)
            RenderQuad();
        else
            RenderSpotFrustum();

        ReleaseResources();
    }
}