fi.conf.ae.gl.texture.GLTextureRoutines.java Source code

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Here is the source code for fi.conf.ae.gl.texture.GLTextureRoutines.java

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/* [LGPL] Copyright 2010, 2011 Gima
    
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
    
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU Lesser General Public License for more details.
    
You should have received a copy of the GNU Lesser General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
package fi.conf.ae.gl.texture;

import java.awt.image.BufferedImage;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.IntBuffer;

import org.lwjgl.BufferUtils;
import org.lwjgl.opengl.GL11;
import org.lwjgl.opengl.GL12;

import fi.conf.ae.image.ImageConversions;
import fi.conf.ae.sys.DirectBuffers;

public class GLTextureRoutines {

    private static IntBuffer textureIDbuffer;

    static {
        allocateNewTextureIDBuffer(4);
    }

    private static void allocateNewTextureIDBuffer(int size) {
        if (textureIDbuffer != null)
            DirectBuffers.freeNativeBufferMemory(textureIDbuffer);
        textureIDbuffer = DirectBuffers.allocateByteBuffer(size << 2).order(ByteOrder.nativeOrder()).asIntBuffer();
    }

    /**
     * Request unused OpenGL texture ID's.
     * 
     * @param count - How many texture IDs are being requested.
     * @return Requested texture ID's as integer array.
     */
    public static int[] allocateGLTextureIDs(int count) {
        if (count > textureIDbuffer.capacity()) {
            allocateNewTextureIDBuffer(count);
        }

        textureIDbuffer.clear();
        textureIDbuffer.limit(count);

        GL11.glGenTextures(textureIDbuffer);

        int[] textureIDs = new int[count];

        for (int i = 0; i < count; i++) {
            if (!textureIDbuffer.hasRemaining())
                break;
            textureIDs[i] = textureIDbuffer.get();

            // preset this texture's minification and magnification filter
            int prevTextureID = bindTexture(textureIDs[i]);
            //         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);
            GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_MIN_FILTER, GL11.GL_LINEAR);
            GL11.glTexParameteri(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_MAG_FILTER, GL11.GL_NEAREST);

            bindTexture(prevTextureID);
        }

        return textureIDs;
    }

    public static int bindTexture(int glTextureID) {
        int prevTextureID = getBoundTextureID();
        GL11.glBindTexture(GL11.GL_TEXTURE_2D, glTextureID);
        return prevTextureID;
    }

    public static int getBoundTextureID() {
        return GL11.glGetInteger(GL11.GL_TEXTURE_BINDING_2D);
    }

    /**
     * Request one unused OpenGL texture ID.
     * 
     * @return Requested texture ID.
     */
    public static int allocateTextureID() {
        return allocateGLTextureIDs(1)[0];
    }

    /**
     * Deallocate OpenGL texture ID's so they can be reused.
     * 
     * @param textureIDs - Integer array of texture ID's to be "returned" to OpenGL.
     */
    public static void deallocateGLTextureIDs(int[] textureIDs) {

        if (textureIDs.length > textureIDbuffer.capacity()) {
            textureIDbuffer = BufferUtils.createIntBuffer(textureIDs.length);
        }

        textureIDbuffer.clear();

        GL11.glDeleteTextures(textureIDbuffer);
    }

    public static void deallocateGLTextureID(Integer glTextureID) {
        deallocateGLTextureIDs(new int[] { glTextureID });
    }

    public static int createTexture(byte[] imageData, int width, int height) {
        int textureID = GLTextureRoutines.allocateTextureID();
        initializeTexture(textureID, imageData, width, height);
        return textureID;
    }

    public static int createTexture(BufferedImage bufferedImage) {
        return createTexture(ImageConversions.convertBIToBGRABytes(bufferedImage), bufferedImage.getWidth(),
                bufferedImage.getHeight());
    }

    public static void initializeTexture(int textureID, byte[] imageData, int width, int height) {

        ByteBuffer byteBuffer = BufferUtils.createByteBuffer(width * height * 4);

        byteBuffer.put(imageData);
        byteBuffer.flip(); // rewind buffer, set limit, remove mark

        int prevTextureID = bindTexture(textureID);

        GL11.glTexImage2D(GL11.GL_TEXTURE_2D, 0, 4, width, height, 0, GL12.GL_BGRA, GL11.GL_UNSIGNED_BYTE,
                byteBuffer);

        bindTexture(prevTextureID);
    }
}