com.bitfire.postprocessing.filters.Glow.java Source code

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Here is the source code for com.bitfire.postprocessing.filters.Glow.java

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/*******************************************************************************
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ******************************************************************************/

package com.bitfire.postprocessing.filters;

import com.badlogic.gdx.graphics.Texture;
import com.badlogic.gdx.math.Vector2;
import com.bitfire.utils.ShaderLoader;

/** Scattering Light effect.
 * @see <a href="https://medium.com/community-play-3d/god-rays-whats-that-5a67f26aeac2">https://medium.com/community-play-3d/god-
 *      rays-whats-that-5a67f26aeac2</a>
 * @author Toni Sagrista **/
public final class Glow extends Filter<Glow> {
    // Number of light supported
    public static int N = 30;
    private Vector2 viewport;

    private float[] lightPositions;
    private float[] lightViewAngles;
    private float[] lightColors;
    private int nLights;
    private int nSamples = 30;
    private float textureScale = 1f;

    private Texture lightGlowTexture;

    public enum Param implements Parameter {
        // @formatter:off
        Texture("u_texture0", 0), LightGlowTexture("u_texture1", 0), LightPositions("u_lightPositions",
                2), LightViewAngles("u_lightViewAngles", 1), LightColors("u_lightColors", 3), Viewport("u_viewport",
                        2), NLights("u_nLights", 0), NSamples("u_nSamples", 0), TextureScale("u_textureScale", 0);
        // @formatter:on

        private String mnemonic;
        private int elementSize;

        private Param(String mnemonic, int arrayElementSize) {
            this.mnemonic = mnemonic;
            this.elementSize = arrayElementSize;
        }

        @Override
        public String mnemonic() {
            return this.mnemonic;
        }

        @Override
        public int arrayElementSize() {
            return this.elementSize;
        }
    }

    public Glow(int width, int height) {
        super(ShaderLoader.fromFile("screenspace", "lightglow"));
        lightPositions = new float[N * 2];
        lightViewAngles = new float[N];
        lightColors = new float[N * 3];
        viewport = new Vector2(width, height);
        rebind();
    }

    public void setViewportSize(float width, float height) {
        this.viewport.set(width, height);
        setParam(Param.Viewport, this.viewport);
    }

    public void setLightPositions(int nLights, float[] vec) {
        this.nLights = nLights;
        this.lightPositions = vec;
        setParam(Param.NLights, this.nLights);
        setParamv(Param.LightPositions, this.lightPositions, 0, N * 2);
    }

    public void setLightViewAngles(float[] ang) {
        this.lightViewAngles = ang;
        setParamv(Param.LightViewAngles, this.lightViewAngles, 0, N);
    }

    public void setLightColors(float[] colors) {
        this.lightColors = colors;
        setParamv(Param.LightColors, this.lightColors, 0, N * 3);
    }

    public void setNSamples(int nSamples) {
        this.nSamples = nSamples;
        setParam(Param.NSamples, nSamples);
    }

    public void setTextureScale(float scl) {
        this.textureScale = scl;
        setParam(Param.TextureScale, textureScale);
    }

    public void setLightGlowTexture(Texture tex) {
        lightGlowTexture = tex;
        setParam(Param.LightGlowTexture, u_texture1);
    }

    public Texture getLightGlowTexture() {
        return lightGlowTexture;
    }

    @Override
    public void rebind() {
        // Re-implement super to batch every parameter
        setParams(Param.Texture, u_texture0);
        setParams(Param.LightGlowTexture, u_texture1);
        setParams(Param.NLights, nLights);
        setParams(Param.NSamples, nSamples);
        setParams(Param.TextureScale, textureScale);
        setParams(Param.Viewport, viewport);
        setParamsv(Param.LightPositions, lightPositions, 0, N * 2);
        setParamsv(Param.LightViewAngles, lightViewAngles, 0, N);
        setParamsv(Param.LightColors, lightColors, 0, N * 3);
        endParams();
    }

    @Override
    protected void onBeforeRender() {
        inputTexture.bind(u_texture0);
        if (lightGlowTexture != null)
            lightGlowTexture.bind(u_texture1);
    }
}