Develop Reference

Object not draw properly in openGl Es

I am drawing the 3D object but its not drawing correctly. Original 3D file does not have diagonally but When I am drawing then its showing the diagonal. Please help me to why its drawing the diagonal.
See this link : http://i.stack.imgur.com/Q4plC.png
Code
public void draw(GL10 gl) {
//gl.glColor4f(0.0f, 1.0f, 0.0f, 0.5f);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
gl.glDrawArrays(3, 0, v.size()/3);
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDisable(GL10.GL_CULL_FACE);
}
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
model.loadGLTexture(gl, context);
gl.glEnable(GL10.GL_TEXTURE_2D);
gl.glClearColor(1.0f, 0.0f, 1.0f, 1.0f);
gl.glClearDepthf(1.0f);
gl.glEnable(GL10.GL_DEPTH_TEST);
gl.glDepthFunc(GL10.GL_LEQUAL);
gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_NICEST);
gl.glShadeModel(GL10.GL_SMOOTH);
}
/**
* Here we do our drawing
*/
public void onDrawFrame(GL10 gl) {
//Clear Screen And Depth Buffer
gl.glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
gl.glLoadIdentity();
gl.glTranslatef(0.0f, 0.0f, 0); //Move down 1.2 Unit And Into The Screen 6.0
gl.glRotatef(xrot, 1.0f, 0.0f, 0.0f); //X
gl.glRotatef(yrot, 0.0f, 1.0f, 0.0f); //Y
model.draw(gl); //Draw the square
xrot += xspeed;
yrot += yspeed;
}
/**
* If the surface changes, reset the view
*/
public void onSurfaceChanged(GL10 gl, int width, int height) {
if(height == 0) { //Prevent A Divide By Zero By
height = 1; //Making Height Equal One
}
gl.glViewport(0, 0, width, height); //Reset The Current Viewport
gl.glMatrixMode(GL10.GL_PROJECTION); //Select The Projection Matrix
gl.glLoadIdentity(); //Reset The Projection Matrix
//Calculate The Aspect Ratio Of The Window
GLU.gluPerspective(gl, 45.0f, width/height, 0.1f, 500.0f);
gl.glMatrixMode(GL10.GL_MODELVIEW); //Select The Modelview Matrix
gl.glLoadIdentity(); //Reset The Modelview Matrix
}
Thanks in advance.

Check the exact order of the vertices in vertexBuffer.
If the order jumped over the diagonal way on the rectangle, it will draw the diagonal line.

drawing a square in open gles

ı try to draw a square.. but when ı run the code, ı see a tringle , not a square... :)) what is the problem here???
public class MyGL20Renderer implements GLSurfaceView.Renderer {
private FloatBuffer square1;
private void initShapes(){
float square1Coords[]={
-0.5f, -0.5f, 0.0f, // 0. left-bottom
0.5f, -0.5f, 0.0f, // 1. right-bottom
0.0f, 0.0f, 0.0f, // 2. left-top
0.5f, 0.5f, 0.0f // 3. right-top
};
// initialize vertex Buffer for square
ByteBuffer vbb4 = ByteBuffer.allocateDirect(
// (# of coordinate values * 4 bytes per float)
square1Coords.length * 4);
vbb4.order(ByteOrder.nativeOrder());
square1 = vbb4.asFloatBuffer();
square1.put(square1Coords);
square1.position(0);
}
.
.
.
.
public void onDrawFrame(GL10 gl) {
// Redraw background color
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
// Draw the square
gl.glColor4f(0.0f, 0.0f, 1.0f, 0.0f); //blue
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, square1);
gl.glDrawArrays(GL10.GL_TRIANGLES, 0, 4);
}

You're specifying GL_TRIANGLES but only have four vertices. Try six.
Or use GL_TRIANGLE_STRIP.

Left top point seem to be wrong, should be -0.5, 0.5, 0.0 and I also agree with genpfault that think you should use GL_TRIANGLE_STRIP

ok.. ı found a way to solve the problem, ı think..
//this is our Square class
public class Square {
private FloatBuffer vertexBuffer; // buffer holding the vertices
private float vertices[] = {
-0.3f, -0.3f, 0.0f, // 0. left-bottom
0.3f, -0.3f, 0.0f, // 1. right-bottom
-0.3f, 0.3f, 0.0f, // 2. left-top
0.3f, 0.3f, 0.0f // 3. right-top
};
public Square() {
// a float has 4 bytes so we allocate for each coordinate 4 bytes
ByteBuffer vertexByteBuffer = ByteBuffer.allocateDirect(vertices.length * 4);
vertexByteBuffer.order(ByteOrder.nativeOrder());
// allocates the memory from the byte buffer
vertexBuffer = vertexByteBuffer.asFloatBuffer();
// fill the vertexBuffer with the vertices
vertexBuffer.put(vertices);
// set the cursor position to the beginning of the buffer
vertexBuffer.position(0);
}
/** The draw method for the square with the GL context */
public void draw(javax.microedition.khronos.opengles.GL10 gl) {
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
// set the colour for the square
gl.glColor4f(1.0f, 0.0f, 0.0f, 0.0f); //red
// Point to our vertex buffer
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
// Draw the vertices as triangle strip
gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, 0, vertices.length / 3);
//Disable the client state before leaving
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
}
}
// and this is our renderer class
public class MyRenderer implements GLSurfaceView.Renderer {
// the square to be drawn
private Square square;
public MyRenderer() {
this.square = new Square();
#Override
public void onDrawFrame(GL10 gl) {
// clear Screen and Depth Buffer
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
// Reset the Modelview Matrix
gl.glLoadIdentity();
// Drawing
gl.glTranslatef(0.0f, 0.0f, -5.0f);
// Draw the square
square.draw(gl);
}
#Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
if(height == 0) { //Prevent A Divide By Zero By
height = 1; //Making Height Equal One
}
gl.glViewport(0, 0, width, height); //Reset The Current Viewport
gl.glMatrixMode(GL10.GL_PROJECTION); //Select The Projection Matrix
gl.glLoadIdentity(); //Reset The Projection Matrix
//Calculate The Aspect Ratio Of The Window
GLU.gluPerspective(gl, 45.0f, (float)width / (float)height, 0.1f, 100.0f);
gl.glMatrixMode(GL10.GL_MODELVIEW); //Select The Modelview Matrix
gl.glLoadIdentity(); //Reset The Modelview Matrix
}
#Override
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
}
}

android/openGL: fill a 2d viewport with a square

What I've managed to accomplish so far is:
Initialise the GLSurfaceView/Renderer
Draw a triangle on the screen
Render a square/rectangle on the screen
Add a bitmap texture to the screen
Ensure PNG transparency is honoured when rendering
Automatically scale the triangles so they show up correctly for all screen sizes
However, after fixing the scaled triangles, the background rectangle (with texture) no longer fills up the screen.
I've been stuck on this for a while now and absolutely baffled to the point I have thrown in the towel.
The main parts I'm unsure about is the use of glFrustumf() and gluLookAt().
#Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
gl.glViewport(0, 0, width, height);
ratio = (float) width / height;
gl.glMatrixMode(GL10.GL_PROJECTION); // set matrix to projection mode
gl.glLoadIdentity(); // reset the matrix to its default state
gl.glFrustumf(-ratio, ratio, -1, 1, 3, 7); // apply the projection matrix
}
#Override
public void onDrawFrame(GL10 gl) {
// Clear the screen
gl.glClear(GL10.GL_COLOR_BUFFER_BIT);
// Set GL_MODELVIEW transformation mode
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity(); // reset the matrix to its default state
// When using GL_MODELVIEW, you must set the camera view
GLU.gluLookAt(gl, 0, 0, -5f, 0f, 0f, 0f, 0.0f, 1.0f, 0.0f);
bg.draw(gl);
// ...
}
If anybody has a moment to take a look at the problem, I've uploaded the files to https://bitbucket.org/koonkii/test_opengl/src so you don't have to recreate the code by copy-pasting.

GLU.gluLookAt(gl, 0, 0, -5f, 0f, 0f, 0f, 0.0f, 1.0f, 0.0f);
Try to change -5f to 0, what you're saying here is displace the camera 5 units back, therefore unless you're doing an orthogonal projection (which I think you're not, try checking out this) what OpenGL is doing is scaling your background polygon according to your perspective view, and you see it as 'smaller'.
If you do an orthogonal projection, no matter how much you move your camera in the z axis, you will always see it the same size. This is useful for 2D OpenGL-based games, so do check out the link above.
EDIT: gluPerspective and glOrtho
gluPerspective(GLdouble fovy, GLdouble aspect, GLdouble zNear, GLdouble zFar);
gluPerspective has a parameter called 'fovy', which is basically the 'Field of View in the Y axis'. The field of view expresses the amount of space the camera can see, basically 'expanding' or 'contracting' whatever vertices happen to be before it. A typical human eye has a 45º FOV.
The zNear and zFar express the near and far frustum limits, the frustum being an invisible 'box' which determines which vertices are outside the viewing area.
Aspect determines the ratio between the width and height of the camera.
glOrtho is a special case of gluPerspective in the sense that the FOV is always 0.
gl.glOrthof(0.0f, (float) width, (float) height, 0.0f, 1.0f, -1.0f);
The first four parameters specify the size of the clipping plane (normally the size of the screen), the other two values specifiy the frustum near and far (which you don't need unless you want to hide objects by placing them 'far away'.
I hope this cleared it up a bit for you.

Alright, after a good nights sleep and applying RedOrav's advice regarding orthogonal projection, I did more browsing into it and got it working!
The code snippets given by RedOrav did actually work, however after switching to the orthogonal projection I was still drawing the squares and triangles as small as 0.15f in width. Barely be visible as it's less than 1 pixel wide!
After changing the background/square/triangle code to something more reasonable (30.0f), they showed up!
Played around with the code a bit more and got positioning working properly. I've submitted the code to bitbucket for those who want to check out a working copy of the project.
The reason why I needed G.getYPos() is because the bottom coordinate = 0, and top is screen height. Couldn't figure out a nicer way of inverting it without turning all the textures upside-down.
The important initialisation parts are:
Global helper
public class G {
public static float ratio;
public static int width, height;
/** The texture pointer */
public static int[] textures = new int[3];
final static int TEXTURE_DEFAULT = 0;
final static int TEXTURE_BG = 1;
final static int TEXTURE_ANDROID = 2;
final static int TEXTURE_TURTLE = 3;
/**
* Since (bottom = 0, top = height), we need to invert the values so they make sense logically.
*/
public static int getYPos(int top) {
return G.height - top;
}
}
Renderer class
#Override
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
this.loadGLTextures(gl);
gl.glClearColor(1.0f, 0.0f, 0.0f, 1.0f); //Red Background
}
#Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
gl.glViewport(0, 0, width, height);
// Save these for global use.
G.width = width;
G.height = height;
G.ratio = (float) width / height;
// Set up orthogonal viewport and make adjustments for screen ratio
gl.glViewport(0, 0, width, height);
gl.glMatrixMode(GL10.GL_PROJECTION);
gl.glLoadIdentity();
GLU.gluOrtho2D(gl, 0, width, 0, height); // The parameters are weird but bottom = 0 so we need an inverter function G.
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
// Start setting up the constructs we need
bg = new Background();
squares = new ArrayList<Square>();
squares.add(new Square(width / 2, G.getYPos(0))); // middle/top of the screen
squares.add(new Square(width / 2, G.height /2)); // center of the screen
triangles = new ArrayList<Triangle>();
triangles.add(new Triangle(0, G.getYPos(0))); // top left
triangles.add(new Triangle(width, G.getYPos(height))); // bottom right
triangles.add(new Triangle(width /2, height /2)); // middle
}
#Override
public void onDrawFrame(GL10 gl) {
// Clear the screen
gl.glClear(GL10.GL_COLOR_BUFFER_BIT);
bg.draw(gl);
for (Square s : squares) {
s.draw(gl);
}
// Draw correctly scaled triangles
for (Triangle t : triangles) {
t.draw(gl);
}
try {
Thread.sleep(400);
}
catch (InterruptedException e) {
}
}
/**
* Loads the textures up.
*/
public void loadGLTextures(GL10 gl) {
int[] texture_map = new int[] { R.drawable.bg_game, R.drawable.ic_launcher };
Bitmap bitmap;
// generate one texture pointer, keep 0 as blank/default
gl.glGenTextures(texture_map.length, G.textures, 0);
for (int i = 0; i < texture_map.length; i++) {
// loading texture
bitmap = BitmapFactory.decodeResource(context.getResources(), texture_map[i]);
// ...and bind it to our array
gl.glBindTexture(GL10.GL_TEXTURE_2D, G.textures[i +1]);
// create nearest filtered texture
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_LINEAR);
// Use Android GLUtils to specify a two-dimensional texture image from our bitmap
GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmap, 0);
// Clean up
bitmap.recycle();
}
}
Background class
p
ublic class Background {
private FloatBuffer vertexBuffer; // buffer holding the vertices
private float vertices[] = {
-1.0f, -1.0f, 0.0f, // V1 - bottom left
-1.0f, 1.0f, 0.0f, // V2 - top left
1.0f, -1.0f, 0.0f, // V3 - bottom right
1.0f, 1.0f, 0.0f // V4 - top right
};
private FloatBuffer textureBuffer; // buffer holding the texture coordinates
private float texture[] = {
// Mapping coordinates for the vertices
0.0f, 1.0f, // top left (V2)
0.0f, 0.0f, // bottom left (V1)
1.0f, 1.0f, // top right (V4)
1.0f, 0.0f // bottom right (V3)
};
public Background() {
// Recalculate the vertices so they fit the screen
vertices[0] = 0; // v1 left
vertices[1] = G.height; // v1 bottom
vertices[3] = 0; // v2 left
vertices[4] = 0; // v2 top
vertices[6] = G.width; // v3 right
vertices[7] = G.height; // v3 bottom
vertices[9] = G.width; // v4 right
vertices[10] = 0; // v4 top
// a float has 4 bytes so we allocate for each coordinate 4 bytes
ByteBuffer byteBuffer = ByteBuffer.allocateDirect(vertices.length * 4);
byteBuffer.order(ByteOrder.nativeOrder());
// allocates the memory from the byte buffer
vertexBuffer = byteBuffer.asFloatBuffer();
// fill the vertexBuffer with the vertices
vertexBuffer.put(vertices);
// set the cursor position to the beginning of the buffer
vertexBuffer.position(0);
byteBuffer = ByteBuffer.allocateDirect(texture.length * 4);
byteBuffer.order(ByteOrder.nativeOrder());
textureBuffer = byteBuffer.asFloatBuffer();
textureBuffer.put(texture);
textureBuffer.position(0);
}
public void draw(GL10 gl) {
gl.glEnable(GL10.GL_TEXTURE_2D); // Twig;
// Bind the previously generated texture
gl.glBindTexture(GL10.GL_TEXTURE_2D, G.textures[G.TEXTURE_BG]);
// Point to our buffers
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
// Point to our vertex buffer
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, textureBuffer);
// Draw the vertices as triangle strip
gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, 0, vertices.length / 3);
//Disable the client state before leaving
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
gl.glDisable(GL10.GL_TEXTURE_2D); // twig;
}
}
Square class
Very similar to background except it has a position and applies alpha transparency.
public class Square {
private FloatBuffer vertexBuffer; // buffer holding the vertices
private float vertices[] = {
-1.0f, -1.0f, 0.0f, // V1 - bottom left
-1.0f, 1.0f, 0.0f, // V2 - top left
1.0f, -1.0f, 0.0f, // V3 - bottom right
1.0f, 1.0f, 0.0f // V4 - top right
};
private FloatBuffer textureBuffer; // buffer holding the texture coordinates
private float texture[] = {
// Mapping coordinates for the vertices
0.0f, 1.0f, // top left (V2)
0.0f, 0.0f, // bottom left (V1)
1.0f, 1.0f, // top right (V4)
1.0f, 0.0f // bottom right (V3)
};
public Square(float posX, float posY) {
float w = 30f;
float h = w;
vertices[0] = posX - w; // left
vertices[3] = posX - w;
vertices[6] = posX + w; // right
vertices[9] = posX + w;
vertices[1] = posY - h; // top
vertices[4] = posY + h;
vertices[7] = posY - h; // bottom
vertices[10] = posY + h;
// a float has 4 bytes so we allocate for each coordinate 4 bytes
ByteBuffer byteBuffer = ByteBuffer.allocateDirect(vertices.length * 4);
byteBuffer.order(ByteOrder.nativeOrder());
// allocates the memory from the byte buffer
vertexBuffer = byteBuffer.asFloatBuffer();
// fill the vertexBuffer with the vertices
vertexBuffer.put(vertices);
// set the cursor position to the beginning of the buffer
vertexBuffer.position(0);
byteBuffer = ByteBuffer.allocateDirect(texture.length * 4);
byteBuffer.order(ByteOrder.nativeOrder());
textureBuffer = byteBuffer.asFloatBuffer();
textureBuffer.put(texture);
textureBuffer.position(0);
}
/** The draw method for the square with the GL context */
public void draw(GL10 gl) {
// Enable alpha transparency
gl.glEnable(GL10.GL_BLEND);
gl.glBlendFunc(GL10.GL_ONE, GL10.GL_ONE_MINUS_SRC_ALPHA);
// bind the previously generated texture
gl.glEnable(GL10.GL_TEXTURE_2D); // Twig;
gl.glBindTexture(GL10.GL_TEXTURE_2D, G.textures[G.TEXTURE_ANDROID]);
// Point to our buffers
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
// reset the colour for the square
gl.glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
// Point to our vertex buffer
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, textureBuffer);
// Draw the vertices as triangle strip
gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, 0, vertices.length / 3);
//Disable the client state before leaving
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
// Disable alpha transparency
gl.glDisable(GL10.GL_BLEND);
gl.glBlendFunc(GL10.GL_ONE, GL10.GL_ZERO);
gl.glDisable(GL10.GL_TEXTURE_2D); // twig;
}
}
Triangle class
public class Triangle {
private FloatBuffer vertexBuffer; // buffer holding the vertices
private float vertices[] = {
-0.5f, -0.5f, 0.0f, // V1 - first vertex (x,y,z)
0.5f, -0.5f, 0.0f, // V2 - second vertex
0.0f, 0.5f, 0.0f // V3 - third vertex
};
public Triangle(float posX, float posY) {
int w = 30;
int h = w;
vertices[0] = posX - (w/2); // left
vertices[3] = posX + (w/2); // right
vertices[6] = posX; // middle
vertices[1] = posY - (h/2); // bottom
vertices[4] = posY - (h/2); // bottom
vertices[7] = posY + (h/2); // top
// a float has 4 bytes so we allocate for each coordinate 4 bytes
ByteBuffer vertexByteBuffer = ByteBuffer.allocateDirect(vertices.length * 4);
vertexByteBuffer.order(ByteOrder.nativeOrder());
// allocates the memory from the byte buffer
vertexBuffer = vertexByteBuffer.asFloatBuffer();
// fill the vertexBuffer with the vertices
vertexBuffer.put(vertices);
// set the cursor position to the beginning of the buffer
vertexBuffer.position(0);
}
public void draw(GL10 gl) {
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
// set the colour for the triangle
gl.glColor4f(0.0f, 0.0f, 1.0f, 1.0f);
// Point to our vertex buffer
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
// Draw the vertices as triangle strip
gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, 0, vertices.length / 3);
// Reset the colour
gl.glColor4f(1.0f, 1.0f, 1.0f, 0.0f);
//Disable the client state before leaving
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
}
}
Hope this helps anyone else having similar issues with starting OpenGL.

Android and glOrthof

I am developing a simple tile world game for Android 2.3. I am trying to set up an orthographic view in opengl but my 1x1 tiles show up oblong -- oriented to the direction of the screen -- if the screen is in vertical position then the square is stretched vertically, if horizontal then it is stretched horizontally. Here is what I have in my onSurfaceChanged method:
gl.glViewport(0, 0, width, height);
gl.glMatrixMode(GL10.GL_PROJECTION);
gl.glLoadIdentity();
gl.glOrthof(0.0f, width, 0.0f, height, 1.0f, 100.0f);
In my onDrawFrame method I have:
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
gl.glLoadIdentity();
GLU.gluLookAt(gl,
0.0f, 0.0f, 6.0f, // eye translation
0.0f, 0.0f, 0.0f, // eye center
0.0f, 1.0f, 0.0f // eye world up
);
// draw objects
From the object onDraw method:
gl.glBindTexture(GL10.GL_TEXTURE_2D, mTextures[0]);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, mFloatVertexBuffer);
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, mTexBuffer);
gl.glEnable(GL10.GL_CULL_FACE);
gl.glShadeModel(GL10.GL_SMOOTH);
gl.glPushMatrix();
gl.glTranslatef(localTranslation.getX(), localTranslation.getY(), localTranslation.getZ());
gl.glScalef(localScale.getX(), localScale.getY(), localScale.getZ());
gl.glRotatef(mAngle, localRotation.getX(), localRotation.getY(), localRotation.getZ());
gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, 0, 4);
gl.glNormal3f(0.0f, 0.0f, -1.0f);
gl.glPopMatrix();
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
I have used the same onSurfaceCreated, onDrawFrame, and onDraw methods with perspective mode and it worked without any distortion to the objects being drawn. I have tried a few different things pulled from the net (like replacing the right/bottom of the ortho call with width/height aspect ratio) but nothing seemed to correct the problem.
Here is what the screen looks like:
Any ideas? What am I missing? All that I want to see are perfect 1x1 squares that I can throw textures on without distortion.

Try this
gl.glViewport(0, 0, width, height);
gl.glMatrixMode(GL10.GL_PROJECTION);
gl.glLoadIdentity();
gl.glOrthof(0.0f, width, 0.0f, height, 1.0f, 100.0f);
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();

Ok this setting is what i use for both iOS and Android but when the screen ratio differs then positions of objects change.
glViewport(0, 0, backingWidth, backingHeight);
glOrthof(-1.0, //LEFT
1.0, //RIGHT
-1.0 * backingHeight / backingWidth, //BOTTOM
1.0 * backingHeight / backingWidth, //TOP
-2.0, //NEAR
100.0); //FAR
NOTE: That this works for normalised coordinates, which is what i use for all of my models.

Drawing quad in OpenGL ES on Android

I am just trying to understand what is going on here. I have a textured quad on the screen but I am really confused why it takes up the entire screen. If my texture is 64X64 and I wanted a quad at the top left of the screen that was 64X64 what would I need to change? Is my viewport or my vertices positions causing it to take up the whole screen?
With changes so far:
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
myquad.loadGLTexture(gl, this.context);
gl.glEnable(GL10.GL_BLEND);
gl.glBlendFunc(gl.GL_SRC_ALPHA, GL10.GL_ONE_MINUS_SRC_ALPHA);
gl.glEnable(GL10.GL_TEXTURE_2D);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_FASTEST);
gl.glDisable(GL10.GL_DEPTH_TEST);
}
public void onSurfaceChanged(GL10 gl, int w, int h) {
width=w;
height=h;
gl.glViewport(0, 0, w, h);
gl.glLoadIdentity();
gl.glOrthof(0.0f, w, 0, h, -1.0f, 1.0f);
}
public void onDrawFrame(GL10 gl) {
// define the color we want to be displayed as the "clipping wall"
gl.glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
// clear the color buffer to show the ClearColor we called above...
gl.glClear(GL10.GL_COLOR_BUFFER_BIT);
gl.glLoadIdentity();
myquad.Draw(gl);
//gl.glTranslatef(.5f, 2.0f, 0.0f);
//gl.glScalef(.5f, .5f, 0);
}
private float vertices[] = {
// Vertices for the square
-1.0f, -1.0f, 0.0f, // 0. left-bottom
1.0f, -1.0f, 0.0f, // 1. right-bottom
-1.0f, 1.0f, 0.0f, // 2. left-top
1.0f, 1.0f, 0.0f // 3. right-top
};
private float texture[] = {
//Mapping coordinates for the vertices
0.0f, 1.0f,
1.0f, 0.0f,
1.0f, 1.0f,
0.0f, 1.0f,
};
public void Draw(GL10 gl)
{
// set the color for the triangle
gl.glColor4f(0.0f, 1.0f, 0.0f, 0.5f);
//Enable the vertex and texture state
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, texturebuffer);
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexbuffer);
//gl.glTranslatex(-20, 0, 0);
// Draw the vertices as triangle strip
gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, 0, vertices.length / 3);
}

Right now you have your projection set up wrong. If you want to draw as if you were dealing with pixels, you would want...
this line
gl.glOrthof(0.0f, w, -h, 0.0f, -1.0f, 1.0f);
to be more like this
gl.glOrthof(0.0f, width, 0.0f, height, -1.0f, 1.0f);
where width and height are the size of your context in pixels.
EDIT:
gl.glOrthof(0.0f, w, -h, 0.0f, -1.0f, 1.0f);
has to be called after each call to glLoadIdentity().
Now you have to adjust your vertex coords. As right now they are set up to render a 1px by 1px box 1px outside the bottom left corner of the screen.