cuchaz.jfxgl.prism.OffscreenBuffer.java Source code

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Here is the source code for cuchaz.jfxgl.prism.OffscreenBuffer.java

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/*************************************************************************
 * Copyright (C) 2017, Jeffrey W. Martin "Cuchaz"
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License Version 2 with
 * the classpath exception, as published by the Free Software Foundation.
 * 
 * See LICENSE.txt in the project root folder for the full license.
 *************************************************************************/
package cuchaz.jfxgl.prism;

import org.lwjgl.opengl.GL11;
import org.lwjgl.opengl.GL30;

public class OffscreenBuffer {

    private JFXGLContext context;
    private int width = 0;
    private int height = 0;
    private int texId = 0;
    private int fboId = 0;
    private boolean quadDirty = true;
    private TexturedQuad quad = null;
    private TexturedQuad.Shader quadShader = null;

    public OffscreenBuffer(JFXGLContext context, int width, int height) {

        if (width <= 0 || height <= 0) {
            throw new IllegalArgumentException(String.format("invalid size: %dx%d", width, height));
        }

        this.context = context;

        // lazily create the quad and shader,
        // in case we want to render this buf in a different context than the one we created it in
        // (vertex arrays aren't shared between contexts, so neither are quads)
        quad = null;
        quadShader = null;
        resize(width, height);
    }

    public boolean resize(int width, int height) {

        if (this.width == width && this.height == height) {
            return false;
        }

        this.width = width;
        this.height = height;

        // resize the texture
        if (texId != 0) {
            context.deleteTexture(texId);
        }
        texId = context.createTexture(width, height);

        // update the framebuf
        if (fboId == 0) {
            fboId = GL30.glGenFramebuffers();
        }
        GL30.glBindFramebuffer(GL30.GL_FRAMEBUFFER, fboId);
        GL30.glFramebufferTexture2D(GL30.GL_FRAMEBUFFER, GL30.GL_COLOR_ATTACHMENT0, GL11.GL_TEXTURE_2D, texId, 0);

        // remove the old quad
        quadDirty = true;

        return true;
    }

    public int getTexId() {
        return texId;
    }

    public int getFboId() {
        return fboId;
    }

    public int bind() {
        int oldFboId = context.getBoundFBO();
        context.bindFBO(fboId);
        return oldFboId;
    }

    public void render() {
        render(0, 0, width, height, false);
    }

    public void render(int x, int y, int w, int h, boolean yflip) {

        if (quadShader == null) {
            quadShader = new TexturedQuad.Shader(context);
        }
        quadShader.bind();
        quadShader.setViewPos(x, y);
        quadShader.setViewSize(w, h);
        quadShader.setYFlip(yflip);

        if (quadDirty) {
            quadDirty = false;
            if (quad != null) {
                quad.cleanup();
            }
            quad = new TexturedQuad(0, 0, width, height, texId, quadShader);
        }
        quad.render();
    }

    public void unbind(int oldFboId) {
        context.bindFBO(oldFboId);
    }

    public void cleanup() {
        context.deleteTexture(texId);
        if (fboId != 0) {
            GL30.glDeleteFramebuffers(fboId);
        }
        if (quad != null) {
            quad.cleanup();
        }
        if (quadShader != null) {
            quadShader.cleanup();
        }
    }
}