Global-Gam-Jam-2017/src/globalgamejam/render/Texture.java

package globalgamejam.render;
import static org.lwjgl.opengl.GL11.*;
import static org.lwjgl.opengl.GL12.*;

import java.awt.*;
import java.awt.image.*;
import java.io.*;
import java.nio.*;

import javax.imageio.*;

import org.lwjgl.*;
import org.lwjgl.opengl.GL12;

/**
 * Class created by MrDev023 (Florian RICHER) on 14/01/2017
 */
public class Texture {

	private static final int BYTES_PER_PIXEL = 4;//3 for RGB, 4 for RGBA
	public int width, height;
	int id;
	
	public Texture(int width,int height,int id){
		this.id = id;
		this.width = width;
		this.height = height;
	}

	public static Texture loadFont(String text, Color color, String font, int size){
		Font f_font = new Font(font, Font.PLAIN, size);

		// to get the width of the text
		BufferedImage img = new BufferedImage(1, 1, BufferedImage.TYPE_INT_ARGB);
		FontMetrics fm = img.getGraphics().getFontMetrics(f_font);

		int width = fm.stringWidth(text);
		int height = fm.getHeight();

		final BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_ARGB);
//		makeTransparent(image);

		Graphics g = image.getGraphics();
		g.setFont(f_font);
		g.setColor(color);
		g.drawString(text, 0, size);
		g.dispose();

		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); //4 for RGBA, 3 for RGB

		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(); //FOR THE LOVE OF GOD DO NOT FORGET THIS

		// You now have a ByteBuffer filled with the color data of each pixel.
		// Now just create a texture ID and bind it. Then you can load it using
		// whatever OpenGL method you want, for example:

		int textureID = glGenTextures(); //Generate texture ID
		glBindTexture(GL_TEXTURE_2D, textureID); //Bind texture ID

		//Setup wrap mode
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL12.GL_CLAMP_TO_EDGE);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL12.GL_CLAMP_TO_EDGE);

		//Setup texture scaling filtering
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);

		//Send texel data to OpenGL
		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, image.getWidth(), image.getHeight(), 0, GL_RGBA, GL_UNSIGNED_BYTE, buffer);

		glBindTexture(GL_TEXTURE_2D, 0);

		return new Texture(image.getWidth(),image.getHeight(),textureID);
	}
	
	public static Texture loadTexture(String path){
		try {
			BufferedImage image = ImageIO.read(new File(path));
			int width = image.getWidth();
			int height = image.getHeight();
			int[] pixels = new int[width * height];
			
			image.getRGB(0, 0, width, height, pixels, 0,width);
			
			int[] data = new int[pixels.length];
			for (int i = 0; i < data.length; i++) {
				int a = (pixels[i] & 0xff000000) >> 24;
				int r = (pixels[i] & 0xff0000) >> 16;
				int g = (pixels[i] & 0xff00) >> 8;
				int b = (pixels[i] & 0xff);
				
				data[i] = a << 24 | b << 16 | g << 8 | r;
			}
			
			IntBuffer buffer = BufferUtils.createIntBuffer(data.length);
			buffer.put(data);
			buffer.flip();
			
			int id = glGenTextures();
			glBindTexture(GL_TEXTURE_2D, id);
			
			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
			
			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
			glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
			
			glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, buffer);
			
			glBindTexture(GL_TEXTURE_2D, 0);

			System.out.println("Texture loaded ! " + width + "x" + height + " id:" + id);
			
			return new Texture(width, height, id);
		} catch (IOException e) {
			e.printStackTrace();
			return null;
		}
	}

	public int getWidth() {
		return width;
	}

	public int getHeight() {
		return height;
	}

	public int getID(){
		return id;
	}
	
	public void bind(){
		if(!glIsEnabled(GL_TEXTURE_2D))glEnable(GL_TEXTURE_2D);
		glBindTexture(GL_TEXTURE_2D, id);
	}
	
	public void unbind(){
		glBindTexture(GL_TEXTURE_2D, 0);
	}
	
	public void destroy(){
		glDeleteTextures(id);
	}
	
}