Merge pull request #2547 from riccardobl/khxtonemap

KHR pbr neutral tonemap

Author: yaRnMcDonuts

jme3-core/src/main/resources/Common/ShaderLib/Hdr.glsllib

@@ -62,4 +62,30 @@ vec3 HDR_ToneMap(in vec3 color, in float lumAvg, in float a, in float white){
 vec3 HDR_ToneMap2(in vec3 color, in float lumAvg, in float a, in float white){
     float scale = a / (lumAvg + 0.001);
     return (vec3(scale) * color) / (color + vec3(1.0));
+}
+
+// Based on https://github.com/KhronosGroup/ToneMapping/blob/main/PBR_Neutral/pbrNeutral.glsl
+// Input color is non-negative and resides in the Linear Rec. 709 color space.
+// Output color is also Linear Rec. 709, but in the [0, 1] range.
+vec3 HDR_KHRToneMap(in vec3 color, in vec3 exposure, in vec3 gamma) {
+    color *= pow(vec3(2.0), exposure); 
+
+    const float startCompression = 0.8 - 0.04;
+    const float desaturation = 0.15;
+
+    float x = min(color.r, min(color.g, color.b));
+    float offset = x < 0.08 ? x - 6.25 * x * x : 0.04;
+    color -= offset;
+
+    float peak = max(color.r, max(color.g, color.b));
+    if (peak < startCompression) return color;
+
+    const float d = 1. - startCompression;
+    float newPeak = 1. - d * d / (peak + d - startCompression);
+    color *= newPeak / peak;
+
+    float g = 1. - 1. / (desaturation * (peak - newPeak) + 1.);
+    color = mix(color, newPeak * vec3(1, 1, 1), g);
+    color = pow(color, gamma);
+    return color;
 }

jme3-effects/src/main/java/com/jme3/post/filters/KHRToneMapFilter.java

@@ -0,0 +1,135 @@
+/*
+ * Copyright (c) 2009-2012 jMonkeyEngine
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ *
+ * * Neither the name of 'jMonkeyEngine' nor the names of its contributors
+ *   may be used to endorse or promote products derived from this software
+ *   without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package com.jme3.post.filters;
+
+import com.jme3.asset.AssetManager;
+import com.jme3.export.InputCapsule;
+import com.jme3.export.JmeExporter;
+import com.jme3.export.JmeImporter;
+import com.jme3.export.OutputCapsule;
+import com.jme3.material.Material;
+import com.jme3.math.Vector3f;
+import com.jme3.post.Filter;
+import com.jme3.renderer.RenderManager;
+import com.jme3.renderer.ViewPort;
+import java.io.IOException;
+
+/**
+ * Tone-mapping filter that uses khronos neutral pbr tone mapping curve.
+ */
+public class KHRToneMapFilter extends Filter {
+
+    private static final float DEFAULT_EXPOSURE = 0.0f;
+    private static final float DEFAULT_GAMMA = 1.0f;
+    
+    private final Vector3f exposure = new Vector3f(DEFAULT_EXPOSURE, DEFAULT_EXPOSURE, DEFAULT_EXPOSURE);
+    private final Vector3f gamma = new Vector3f(DEFAULT_GAMMA, DEFAULT_GAMMA, DEFAULT_GAMMA);
+
+    /**
+     * Creates a tone-mapping filter with the default exposure and gamma.
+     */
+    public KHRToneMapFilter() {
+        super("KHRToneMapFilter");
+    }
+
+
+    @Override
+    protected boolean isRequiresDepthTexture() {
+        return false;
+    }
+
+    @Override
+    protected void initFilter(AssetManager manager, RenderManager renderManager, ViewPort vp, int w, int h) {
+        material = new Material(manager, "Common/MatDefs/Post/KHRToneMap.j3md");
+        material.setVector3("Exposure", exposure);
+        material.setVector3("Gamma", gamma);
+    }
+
+    @Override
+    protected Material getMaterial() {
+        return material;
+    }
+
+    /**
+     * Set the exposure for the tone mapping.
+     * 
+     * @param whitePoint The exposure vector.
+     */
+    public void setExposure(Vector3f whitePoint) {
+        this.exposure.set(whitePoint);
+    }
+
+    /**
+     * Get the exposure for the tone mapping.
+     * 
+     * @return The exposure vector.
+     */
+    public Vector3f getExposure() {
+        return exposure;
+    }
+
+    
+    /**
+     * Set the gamma for the tone mapping.
+     * 
+     * @param gamma The gamma vector.
+     */
+    public void setGamma(Vector3f gamma) {
+        this.gamma.set(gamma);
+    }
+
+    /**
+     * Get the gamma for the tone mapping.
+     * 
+     * @return The gamma vector.
+     */
+    public Vector3f getGamma() {
+        return gamma;
+    }
+
+    @Override
+    public void write(JmeExporter ex) throws IOException {
+        super.write(ex);
+        OutputCapsule oc = ex.getCapsule(this);
+        oc.write(exposure, "exposure", new Vector3f(DEFAULT_EXPOSURE, DEFAULT_EXPOSURE, DEFAULT_EXPOSURE));
+        oc.write(gamma, "gamma", new Vector3f(DEFAULT_GAMMA, DEFAULT_GAMMA, DEFAULT_GAMMA));
+    }
+
+    @Override
+    public void read(JmeImporter im) throws IOException {
+        super.read(im);
+        InputCapsule ic = im.getCapsule(this);
+        exposure.set((Vector3f)ic.readSavable("exposure", new Vector3f(DEFAULT_EXPOSURE, DEFAULT_EXPOSURE, DEFAULT_EXPOSURE)));
+        gamma.set((Vector3f)ic.readSavable("gamma", new Vector3f(DEFAULT_GAMMA, DEFAULT_GAMMA, DEFAULT_GAMMA)));
+    }
+
+}

jme3-effects/src/main/resources/Common/MatDefs/Post/KHRToneMap.frag

@@ -0,0 +1,43 @@
+#extension GL_ARB_texture_multisample : enable
+#import "Common/ShaderLib/GLSLCompat.glsllib"
+#import "Common/ShaderLib/Hdr.glsllib"
+
+
+uniform vec3 m_Exposure;
+uniform vec3 m_Gamma;
+varying vec2 texCoord;
+ 
+vec3 applyCurve(in vec3 x) {    
+    return HDR_KHRToneMap(x, m_Exposure, m_Gamma);
+}
+
+
+#ifdef NUM_SAMPLES
+
+uniform sampler2DMS m_Texture;
+
+vec4 applyToneMap() {
+    ivec2 iTexC = ivec2(texCoord * vec2(textureSize(m_Texture)));
+    vec4 color = vec4(0.0);
+    for (int i = 0; i < NUM_SAMPLES; i++) {
+        vec4 hdrColor = texelFetch(m_Texture, iTexC, i);
+        vec3 ldrColor = applyCurve(hdrColor.rgb);
+        color += vec4(ldrColor, hdrColor.a);
+    }
+    return color / float(NUM_SAMPLES);
+}
+
+#else
+ 
+uniform sampler2D m_Texture;
+ 
+vec4 applyToneMap() {
+    vec4 texVal = texture2D(m_Texture, texCoord);
+    return vec4(applyCurve(texVal.rgb) , texVal.a);
+}
+ 
+#endif
+
+void main() {
+    gl_FragColor = applyToneMap();
+}

jme3-effects/src/main/resources/Common/MatDefs/Post/KHRToneMap.j3md

@@ -0,0 +1,24 @@
+MaterialDef KHRToneMap {
+
+    MaterialParameters {
+        Int BoundDrawBuffer
+        Int NumSamples
+        Int NumSamplesDepth
+        Texture2D Texture
+        Vector3 Gamma
+        Vector3 Exposure
+    }
+
+    Technique {
+        VertexShader     GLSL300 GLSL150 GLSL100:   Common/MatDefs/Post/Post.vert
+        FragmentShader   GLSL300 GLSL150 GLSL100: Common/MatDefs/Post/KHRToneMap.frag
+
+        WorldParameters {
+        }
+
+        Defines {
+            BOUND_DRAW_BUFFER: BoundDrawBuffer
+            NUM_SAMPLES : NumSamples
+        }
+    }
+}