com.kauridev.lunarfever.graphics.TextureLoader.java Source code

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Here is the source code for com.kauridev.lunarfever.graphics.TextureLoader.java

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/*
 * This file is part of the lunar-fever package.
 *
 * Copyright (c) 2014 Eric Fritz
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
 * and associated documentation files (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all copies or
 * substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

package com.kauridev.lunarfever.graphics;

import com.kauridev.lunarfever.util.FileUtil;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.HashMap;
import java.util.Map;
import javax.imageio.ImageIO;
import org.lwjgl.BufferUtils;
import org.lwjgl.opengl.GL11;

/**
 * @author Eric Fritz
 */
public class TextureLoader {
    private static final int BYTES_PER_PIXEL = 4;

    private static Map<String, Texture> cache = new HashMap<>();

    public static Texture loadTexture(String file) {
        Texture texture = cache.get(file);

        if (texture != null && texture.getTexture().valid()) {
            return texture;
        }

        BufferedImage image = loadImage(file);

        GL11.glEnable(GL11.GL_TEXTURE_2D);
        int id = GL11.glGenTextures();

        // bind
        GL11.glBindTexture(GL11.GL_TEXTURE_2D, id);

        // set filter
        GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_MIN_FILTER, GL11.GL_NEAREST);
        GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_MAG_FILTER, GL11.GL_NEAREST);

        // set wrap
        GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_WRAP_S, GL11.GL_CLAMP);
        GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_WRAP_T, GL11.GL_CLAMP);

        // set unpack alignment
        GL11.glPixelStorei(GL11.GL_PACK_ALIGNMENT, 1);
        GL11.glPixelStorei(GL11.GL_UNPACK_ALIGNMENT, 1);

        // send data to gpu
        GL11.glTexImage2D(GL11.GL_TEXTURE_2D, 0, GL11.GL_RGBA, image.getWidth(), image.getHeight(), 0, GL11.GL_RGBA,
                GL11.GL_UNSIGNED_BYTE, loadBuffer(image));

        // Create texture
        texture = new Texture(id, image.getWidth(), image.getHeight());

        cache.put(file, texture);
        return texture;
    }

    private static ByteBuffer loadBuffer(BufferedImage image) {
        int[] pixels = new int[image.getWidth() * image.getHeight()];
        image.getRGB(0, 0, image.getWidth(), image.getHeight(), pixels, 0, image.getWidth());

        ByteBuffer buffer = BufferUtils.createByteBuffer(image.getWidth() * image.getHeight() * BYTES_PER_PIXEL);

        for (int y = 0; y < image.getHeight(); y++) {
            for (int x = 0; x < image.getWidth(); x++) {
                int pixel = pixels[y * image.getWidth() + x];

                buffer.put((byte) ((pixel >> 16) & 0xFF)); // Red component
                buffer.put((byte) ((pixel >> 8) & 0xFF)); // Green component
                buffer.put((byte) (pixel & 0xFF)); // Blue component
                buffer.put((byte) ((pixel >> 24) & 0xFF)); // Alpha component. Only for RGBA
            }
        }

        buffer.flip();

        return buffer;
    }

    private static BufferedImage loadImage(String loc) {
        try {
            return ImageIO.read(FileUtil.getFileAsStream(loc));
        } catch (IOException e) {
            e.printStackTrace();
        }

        return null;
    }
}