Thread: OpenGL Texture won't draw

I have followed a tutorial on how to display an image in OpenGL, and I first had to make a square and then texture it. I have tried

gl.glColor4f(0f,0f,0f,1f);

and that works, I can see the square. But then when I try to texture it, the screen just stays white. What did I do wrong?

Here is the screen with the

gl.glColor4f(0f,0f,0f,1f);

:

lYaCq.jpg

If I apply the texture (using the custom Texture class that the tutorial suggested), the screen is completely white.

Here is my code:

Square.java:

package com.nivangerow.android.reference;
 
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import java.nio.ShortBuffer;
 
import javax.microedition.khronos.opengles.GL10;
 
import android.content.Context;
 
public class Square
{
	final int VERTEX_SIZE = (2+2) *4;
	FloatBuffer vertices;
	ShortBuffer indices;
 
	Texture texture;
 
	GL10 gl;
	Context c;
 
	public Square(GL10 gl, Context context)
	{
		this.gl = gl;
		this.c = context;
 
		ByteBuffer byteBuffer = ByteBuffer.allocateDirect(VERTEX_SIZE * 4);
		byteBuffer.order(ByteOrder.nativeOrder());
		vertices = byteBuffer.asFloatBuffer();
		vertices.put(new float[]{
			10.0f, 10.0f, 0.0f, 0.0f, //bl	
			160.0f, 10.0f, 1.0f, 0.0f, //br	
			160.0f, 160.0f, 1.0f, 1.0f, //tr	
			10.0f, 160.0f, 1.0f, 0.0f, //tl	
		});
		vertices.flip();
 
		vertices.position(0);
 
		byteBuffer = ByteBuffer.allocateDirect(VERTEX_SIZE * 4);
		byteBuffer.order(ByteOrder.nativeOrder());
		indices = byteBuffer.asShortBuffer();
		indices.put(new short[]{
			0, 1, 2, 2, 3, 0
		});
		indices.flip();
 
		indices.position(0);
 
		texture = new Texture("image/picture.png", c, gl);
	}
 
	public void draw()
	{
		gl.glEnable(GL10.GL_TEXTURE_2D);
		texture.bind();
		//gl.glColor4f(0f, 0f, 0f, 1f);
 
		gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
		gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
 
		vertices.position(0);
		gl.glVertexPointer(2, GL10.GL_FLOAT, VERTEX_SIZE, vertices);
		vertices.position(2);
		gl.glTexCoordPointer(2, GL10.GL_FLOAT, VERTEX_SIZE, vertices);
 
		gl.glDrawElements(GL10.GL_TRIANGLES, 6, GL10.GL_UNSIGNED_SHORT, indices);
	}
}

Texture.java

package com.nivangerow.android.reference;
 
import java.io.InputStream;
 
import javax.microedition.khronos.opengles.GL10;
 
import android.content.Context;
import android.content.res.AssetManager;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.opengl.GLUtils;
 
public class Texture {
 
	String texturePath;
	Context context;
	GL10 gl;
 
	int textureId;
	int minFilter;
	int magFilter;
	Bitmap texture;
 
	public Texture(String texturePath, Context context, GL10 gl)
	{
		this.gl = gl;
		this.texturePath = texturePath;
		this.context = context;
	}
 
	public void load()
	{
		try{
			AssetManager assetManager = context.getAssets();
			InputStream is = assetManager.open(texturePath);
			texture = BitmapFactory.decodeStream(is);
			gl.glBindTexture(GL10.GL_TEXTURE_2D, textureId);
			GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, texture, 0);
			setFilters(GL10.GL_NEAREST, GL10.GL_NEAREST);
			gl.glBindTexture(GL10.GL_TEXTURE_2D, 0);
		}catch(Exception e)
		{
			e.printStackTrace();
		}
	}
 
	public void reload()
	{
		load();
		bind();
		setFilters(minFilter, magFilter);
		gl.glBindTexture(GL10.GL_TEXTURE_2D, 0);
	}
 
	public void setFilters(int minFilter, int magFilter)
	{
		this.minFilter = minFilter;
		this.magFilter = magFilter;
		gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, minFilter);
		gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MAG_FILTER, magFilter);
	}
 
	public void bind()
	{
		gl.glBindTexture(GL10.GL_TEXTURE_2D, textureId);
	}
 
	public void dispose()
	{
		gl.glBindTexture(GL10.GL_TEXTURE_2D, textureId);
		int[] textureIds = {textureId};
		gl.glDeleteTextures(1, textureIds, 0);
	}
 
}

OpenGLRenderer.java

package com.nivangerow.android.reference;
 
import java.util.Random;
 
import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;
 
import android.content.Context;
import android.opengl.GLSurfaceView.Renderer;
 
public class OpenGLRenderer implements Renderer 
{
	Random rand = new Random();
	int mWidth = 0;
	int mHeight = 0;
 
	Context c;
 
	Square square;
 
	public OpenGLRenderer(Context c)
	{
		this.c = c;
	}
 
	@Override
	public void onDrawFrame(GL10 gl) 
	{
		gl.glClearColor(1, 1, 1, 1);
		gl.glClear(GL10.GL_COLOR_BUFFER_BIT);
		gl.glViewport(0, 0, mWidth, mHeight);
		gl.glMatrixMode(GL10.GL_PROJECTION);
		gl.glLoadIdentity();
		gl.glOrthof(0, mWidth, 0, mHeight, 1, -1);
 
		if(square != null)square.draw();
	}
 
	@Override
	public void onSurfaceChanged(GL10 gl, int width, int height) 
	{
		mWidth = width;
		mHeight = height;
	}
 
	@Override
	public void onSurfaceCreated(GL10 gl, EGLConfig config) 
	{
		square = new Square(gl, c);
	}
 
}

Thanks in advance.