I'm coding on Android Platform. I'm trying to use texture (load image from Assets folder) for triangle. When my app run, it just blank white in triangle (not texture what I want).
I have read some other source that say image must be a power of two. And I have checked, my image is a power of two. (128 x 128). That a reason why make me headache.
Here is my code: (the main code that you should see in onDrawFrame method, It contains code that I use for Render)
package com.test;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;
import android.app.Activity;
import android.content.res.AssetManager;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.opengl.GLSurfaceView;
import android.opengl.GLSurfaceView.Renderer;
import android.opengl.GLUtils;
import android.os.Bundle;
import android.util.Log;
public class TextureTriangleTest extends Activity{
GLSurfaceView glView;
ByteBuffer byteBuffer;
FloatBuffer vertices;
AssetManager assets;
@Override
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
assets = getAssets();
int VERTEX_SIZE = (2+2)*4;
byteBuffer = ByteBuffer.allocateDirect(3*VERTEX_SIZE);
byteBuffer.order(ByteOrder.nativeOrder());
vertices = byteBuffer.asFloatBuffer();
vertices.put(new float[] { 0.0f, 0.0f, 0.0f, 1.0f,
319.0f, 0.0f, 1.0f, 1.0f,
160.0f, 479.0f, 0.5f, 0.0f } );
vertices.flip();
glView = new GLSurfaceView(this);
glView.setRenderer(new Render());
setContentView(glView);
}
class Render implements Renderer{
@Override
public void onDrawFrame(GL10 gl) {
try {
Bitmap bitmap = BitmapFactory.decodeStream(assets.open("bobrgb888.png"));
int textureIds[] = new int[1];
gl.glGenTextures(1, textureIds, 0);
int textureId = textureIds[0];
gl.glBindTexture(GL10.GL_TEXTURE_2D, textureId);
GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmap, 0);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_NEAREST);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MAG_FILTER, GL10.GL_NEAREST);
gl.glBindTexture(GL10.GL_TEXTURE_2D, 0);
bitmap.recycle();
} catch (IOException e) {
Log.d("", "FAILED LOAD FILE");
throw new RuntimeException("Couldn't load asset!");
}
gl.glViewport(0, 0, glView.getWidth(), glView.getHeight());
gl.glClear(GL10.GL_COLOR_BUFFER_BIT);
gl.glMatrixMode(GL10.GL_PROJECTION);
gl.glLoadIdentity();
gl.glOrthof(0, 320, 0, 480, 1, -1);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
int VERTEX_SIZE = (2+2)*4;
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.glDrawArrays(GL10.GL_TRIANGLES, 0, 3);
}
@Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
// TODO Auto-generated method stub
}
@Override
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
// TODO Auto-generated method stub
}
}
}
My code just a simple example. I have debug and all thing is true. (such as: successfully load image). But, I don't know how to debug OpenGL app. (It means : when debug, I can view parameter of variable, but I don't know how it be, because OpenGL is too complicated than Canvas- that you just use one line of code and has result :) )
thanks for help :)
Oh. I have fixed whole my solutions, and below is my full code. I posted here for whom try to read my long post (^^) and need a real solution :) Thanks to SteveL has suggested me :)
In my solution, I have some change:
first. Performance: I put code read texture in onSurfaceCreate.
second. As SteveL say. I'm missing gl.glEnable and I have reseted again gl.glBindTexture.
Thinks again, I see that those error really silly. Just because I'm a newbie of OpenGL :(
package com.test;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;
import android.app.Activity;
import android.opengl.GLSurfaceView;
import android.opengl.GLSurfaceView.Renderer;
import android.os.Bundle;
public class ColorTriangleTest extends Activity{
GLSurfaceView glView;
ByteBuffer byteBuffer;
FloatBuffer vertices;
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
int VERTEX_SIZE = (2+4)*4;
byteBuffer = ByteBuffer.allocateDirect(3*VERTEX_SIZE);
byteBuffer.order(ByteOrder.nativeOrder());
vertices = byteBuffer.asFloatBuffer();
vertices.put(new float[] { 0.0f, 0.0f, 1, 0, 0, 1,
319.0f, 0.0f, 1, 1, 0, 1,
160.0f, 479.0f, 1, 0, 1, 1 });
vertices.flip();
glView = new GLSurfaceView(this);
glView.setRenderer(new Render());
setContentView(glView);
}
class Render implements Renderer {
@Override
public void onDrawFrame(GL10 gl) {
int VERTEX_SIZE = (2+4)*4;
gl.glViewport(0, 0, glView.getWidth(), glView.getHeight());
gl.glClear(GL10.GL_COLOR_BUFFER_BIT);
gl.glMatrixMode(GL10.GL_PROJECTION);
gl.glLoadIdentity();
gl.glOrthof(0, 320, 0, 480, 10, -10);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_COLOR_ARRAY);
vertices.position(0);
gl.glVertexPointer(2, GL10.GL_FLOAT, VERTEX_SIZE, vertices);
vertices.position(2);
gl.glColorPointer(4, GL10.GL_FLOAT, VERTEX_SIZE, vertices);
gl.glDrawArrays(GL10.GL_TRIANGLES, 0, 3);
}
@Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
// TODO Auto-generated method stub
}
@Override
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
// TODO Auto-generated method stub
}
}
}