EDIT OK – I grabbed a device and..guess what…it displays correctly ? Does anyone know why this would be happening on the simulator only ? Thank you.
I am trying to draw an object using glDrawElements on Android. I am using the code below to read in my vertice and indice data and then draw the object in my render method. I am testing this on the simulator rather than a real device.
This is my scene object code :
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import java.nio.IntBuffer;
import java.nio.ShortBuffer;
import javax.microedition.khronos.opengles.GL10;
public class SceneObject {
public FloatBuffer mVertexBuffer;
public FloatBuffer mTextureBuffer;
public ShortBuffer indexBuffer;
public FloatBuffer mMatriceBuffer;
public FloatBuffer mPivotBuffer;
public short[] indicesTest = {0,1,2,3,4,5,3,5,6,7,5,8,7,8,9,10,7,9,11,10,9,12,1,0,13,12,14,15,13,14,14,10,11,15,14,11,0,14,12,16,17,18,19,16,18,18,20,19,21,16,19,22,21,19,22,19,23,4,24,25,25,26,27,25,27,28,4,25,28,5,4,28,5,28,8,29,30,31,29,31,19,29,19,20,32,33,31,32,31,30,32,34,33,35,22,23,36,35,23,37,36,23,37,23,38,39,37,38,40,39,38,41,40,38,41,38,1,42,41,1,12,43,1,42,1,43,17,27,26,26,18,17,44,45,46,46,47,44,48,49,50,51,52,53,53,54,51,55,51,54,54,56,55,57,48,50,50,58,57,52,59,60,60,53,52,59,44,47,47,60,59,61,62,63,63,64,61,65,66,67,67,68,65,69,70,71,71,72,69,66,69,72,72,67,66,73,65,68,68,74,73,70,75,76,76,71,70,75,61,64,64,76,75,77,78,79,79,80,77,81,82,62,62,61,81,83,81,61,61,75,83,84,63,62,62,82,84,63,84,85,86,87,88,89,90,91,92,93,87,87,86,92,94,95,96,96,97,94,98,99,100,100,101,98,102,103,104,104,105,102,106,107,108,108,109,106,110,111,112,78,77,113,114,115,78,112,111,116,117,118,115,119,116,120,121,122,123,123,124,121,125,126,127,127,128,125,129,130,131,132,133,5,5,133,6,5,134,135,135,134,136,134,137,136,137,138,136,129,139,130,139,140,141,140,142,141,137,141,138,141,142,138,141,130,139,143,144,145,144,146,145,147,145,146,144,148,146,148,149,146,146,149,150,151,132,152,153,152,154,154,152,155,152,132,155,132,5,155,155,5,135,156,157,158,158,157,146,146,157,147,159,160,158,158,160,156,34,160,159,149,161,150,161,162,150,162,163,150,150,163,164,163,165,164,165,166,164,166,167,164,164,167,129,167,168,129,169,139,129,129,168,169,154,143,153,145,153,143,170,171,172,173,172,171,174,175,176,177,178,179,180,179,178,178,181,180,182,180,181,175,183,176,184,176,183,185,177,186,179,186,177,171,185,173,186,173,185,187,188,189,190,189,188,191,192,193,194,193,192,195,196,197,198,197,196,196,191,198,193,198,191,192,199,194,200,194,199,201,195,202,197,202,195,188,201,190,202,190,201,203,204,205,206,205,204,207,208,187,188,187,208,208,209,188,201,188,209,189,210,187,207,187,210,210,189,211,212,213,214,215,216,217,218,219,220,221,220,219,222,223,224,225,226,227,228,229,230,231,230,229,232,233,234,235,236,237,238,239,240,241,242,243,123,244,124,245,246,203,204,203,246,247,248,203,249,250,251,252,253,247,248,247,253,159,33,34,254,255,256,256,257,254,255,244,123,123,256,255,244,258,121,121,124,244,259,260,125,125,128,259};
public float[] verticeTest = {20360.8f,20679.5f,611.547f,24248.7f,13527f,1074.93f,24207.4f,23005.5f,1503.19f,9819.59f,14845.7f,8.81875f,11126.3f,13982.2f,32.0718f,8379.01f,17678.5f,0.00115749f,8379.01f,15141.6f,0.00111471f,12137.8f,17973.8f,60.0461f,14591.9f,14509.2f,164.113f,15621.5f,15846.6f,223.075f,15136.7f,18549.5f,194.186f,16918.2f,16705.3f,310.215f,21081.8f,15846.6f,687.576f,19789f,16705.3f,554.435f,18467.9f,19868.7f,433.258f,18354.3f,17001.2f,423.539f,14591.9f,7402.34f,164.113f,13930.5f,9087.62f,131.015f,13039.7f,9096.18f,92.3283f,19110.4f,-8011.43f,490.311f,12811.7f,7228.03f,83.5128f,15621.5f,6064.9f,223.074f,16918.2f,5206.21f,310.215f,21807.5f,-426.492f,768.658f,11221.5f,13854f,34.3347f,12150f,12649.6f,60.4329f,12811.7f,10964.3f,83.513f,13702.6f,10955.8f,120.472f,13930.5f,12823.9f,131.015f,12150f,5542.76f,60.4327f,11119f,4205.31f,31.902f,15341.7f,-15792.9f,206.155f,9819.59f,3346.62f,8.81857f,10735.6f,-21752.5f,23.5976f,8379.01f,3050.73f,0.000981022f,18354.3f,4910.32f,423.538f,19789f,5206.21f,554.434f,21081.8f,6064.9f,687.576f,23336.1f,6399.27f,954.364f,22106.6f,7402.34f,803.393f,22764f,9087.62f,882.485f,22990.5f,10955.8f,910.595f,22764f,12823.9f,882.485f,22106.6f,14509.2f,803.393f,24248.7f,8492.36f,-3249.03f,24207.4f,17415.3f,-3297.97f,24207.4f,23005.5f,1503.19f,24248.7f,13527f,1074.93f,12728.3f,-24463.4f,-4243.56f,15341.7f,-20827.5f,-4117.81f,15341.7f,-15792.9f,206.155f,19110.4f,-13046f,-3833.65f,21807.5f,-5461.09f,-3555.3f,21807.5f,-426.492f,768.658f,19110.4f,-8011.43f,490.311f,15341.7f,-20827.5f,-4117.81f,15341.7f,-15792.9f,206.155f,10735.6f,-26787.1f,-4300.36f,10735.6f,-21752.5f,23.5976f,23336.1f,1364.68f,-3369.59f,23336.1f,6399.27f,954.364f,24883.8f,8123.11f,-2819.08f,24859.5f,16025.8f,-2803.12f,24207.4f,17415.3f,-3297.97f,24248.7f,8492.36f,-3249.03f,13363.4f,-24832.7f,-3813.62f,15976.8f,-21196.8f,-3687.86f,15341.7f,-20827.5f,-4117.81f,12728.3f,-24463.4f,-4243.56f,19745.5f,-13415.3f,-3403.7f,22442.7f,-5830.35f,-3125.36f,21807.5f,-5461.09f,-3555.3f,19110.4f,-13046f,-3833.65f,10915.8f,-27847.5f,-3863.23f,10735.6f,-26787.1f,-4300.36f,23222.6f,-2518.03f,-3057.67f,23336.1f,1364.68f,-3369.59f,10301.8f,-40240.8f,-15469.8f,10482f,-40907.1f,-14694f,10915.8f,-27847.5f,-3863.23f,10735.6f,-26787.1f,-4300.36f,25648.8f,8121.58f,-2817.31f,25624.5f,16024.2f,-2801.34f,24056.1f,-2550.94f,-3019.36f,25678.7f,16560.2f,-2907.29f,25594.2f,17951.2f,-3237.71f,25624.5f,-88046.9f,-92182.7f,25678.7f,-87767f,-92508.6f,25678.7f,16560.2f,-2907.29f,25678.7f,16560.2f,-2907.29f,25624.5f,16024.2f,-2801.34f,25624.5f,-88046.9f,-92182.7f,25624.5f,-88413.1f,-92497.2f,25678.7f,-88133.2f,-92823.1f,24765.7f,-88413.1f,-92497.2f,24820f,-88133.2f,-92823.1f,25678.7f,-88133.2f,-92823.1f,25624.5f,-88413.1f,-92497.2f,24765.7f,-89895.8f,-93770.7f,24820f,-89615.9f,-94096.6f,24820f,-88133.2f,-92823.1f,24765.7f,-88413.1f,-92497.2f,25678.7f,-89596.5f,-94079.9f,25678.7f,-88133.2f,-92823.1f,24820f,-88133.2f,-92823.1f,24820f,-89615.9f,-94096.6f,23222.6f,-93458.9f,-81162.2f,24056.1f,-93491.8f,-81123.9f,24056.1f,-2550.94f,-3019.36f,23222.6f,-2518.03f,-3057.67f,10579.6f,-102089f,-68973.2f,10579f,-102925f,-68042.7f,10482f,-40907.1f,-14694f,10579.6f,-102089f,-68973.2f,10579f,-102925f,-68042.7f,10482f,-41291.8f,-14246f,10579f,-102925f,-68042.7f,10489f,-103571f,-67018.6f,10482f,-41713.9f,-13886.7f,10482f,-41291.8f,-14246f,10489f,-103571f,-67018.6f,8379.01f,-102145f,-69021.7f,10579.6f,-102089f,-68973.2f,10301.8f,-40240.8f,-15469.8f,8379.01f,-68082.6f,-39554.7f,8379.01f,-101057f,-70411.1f,10735.6f,-101057f,-70411.1f,10579.6f,-102089f,-68973.2f,8379.01f,-102145f,-69021.7f,-7490.7f,13527f,1074.93f,-3602.79f,20679.5f,611.547f,-7449.35f,23005.5f,1503.19f,5631.77f,13982.2f,32.0718f,6938.43f,14845.7f,8.81875f,4620.19f,17973.8f,60.0461f,2166.16f,14509.2f,164.113f,1136.48f,15846.6f,223.075f,1621.29f,18549.5f,194.186f,-160.178f,16705.3f,310.215f,-4323.73f,15846.6f,687.576f,-3030.97f,16705.3f,554.435f,-1709.92f,19868.7f,433.258f,-1596.32f,17001.2f,423.539f,2827.51f,9087.62f,131.015f,2166.16f,7402.34f,164.113f,3718.3f,9096.18f,92.3283f,-2352.36f,-8011.43f,490.311f,3946.3f,7228.03f,83.5128f,1136.48f,6064.9f,223.074f,-160.182f,5206.21f,310.215f,-5049.53f,-426.492f,768.658f,5536.51f,13854f,34.3347f,4608.07f,12649.6f,60.4329f,3946.3f,10964.3f,83.513f,3055.44f,10955.8f,120.472f,2827.51f,12823.9f,131.015f,5639.04f,4205.31f,31.902f,4608.07f,5542.76f,60.4327f,1416.3f,-15792.9f,206.155f,6022.45f,-21752.5f,23.5976f,6938.43f,3346.62f,8.81857f,-1596.32f,4910.32f,423.538f,-3030.97f,5206.21f,554.434f,-4323.73f,6064.9f,687.576f,-6578.08f,6399.27f,954.364f,-5348.56f,7402.34f,803.393f,-6006f,9087.62f,882.485f,-6232.44f,10955.8f,910.595f,-6006f,12823.9f,882.485f,-5348.57f,14509.2f,803.393f,-7449.35f,17415.3f,-3297.97f,-7490.7f,8492.36f,-3249.03f,-7449.35f,23005.5f,1503.19f,-7490.7f,13527f,1074.93f,1416.3f,-20827.5f,-4117.81f,4029.77f,-24463.4f,-4243.56f,1416.3f,-15792.9f,206.155f,-5049.53f,-5461.09f,-3555.3f,-2352.36f,-13046f,-3833.65f,-5049.53f,-426.492f,768.658f,-2352.36f,-8011.43f,490.311f,1416.3f,-20827.5f,-4117.81f,1416.3f,-15792.9f,206.155f,6022.45f,-26787.1f,-4300.36f,6022.45f,-21752.5f,23.5976f,-6578.08f,1364.68f,-3369.59f,-6578.08f,6399.27f,954.364f,-8101.47f,16025.8f,-2803.12f,-8125.81f,8123.11f,-2819.08f,-7449.35f,17415.3f,-3297.97f,-7490.7f,8492.36f,-3249.03f,781.19f,-21196.8f,-3687.86f,3394.66f,-24832.7f,-3813.62f,1416.3f,-20827.5f,-4117.81f,4029.77f,-24463.4f,-4243.56f,-5684.64f,-5830.35f,-3125.36f,-2987.47f,-13415.3f,-3403.7f,-5049.53f,-5461.09f,-3555.3f,-2352.36f,-13046f,-3833.65f,5842.26f,-27847.5f,-3863.23f,6022.45f,-26787.1f,-4300.36f,-6464.54f,-2518.03f,-3057.67f,-6578.08f,1364.68f,-3369.59f,6276.06f,-40907.1f,-14694f,6456.25f,-40240.8f,-15469.8f,5842.26f,-27847.5f,-3863.23f,6022.45f,-26787.1f,-4300.36f,-8866.45f,16024.2f,-2801.34f,-8890.79f,8121.58f,-2817.31f,-7298.12f,-2550.94f,-3019.36f,-8920.72f,16560.2f,-2907.29f,-8836.13f,17951.2f,-3237.71f,-8920.72f,-87767f,-92508.6f,-8866.45f,-88046.9f,-92182.7f,-8920.72f,16560.2f,-2907.29f,-8866.45f,16024.2f,-2801.34f,-8920.72f,16560.2f,-2907.29f,-8866.45f,-88046.9f,-92182.7f,-8920.72f,-88133.2f,-92823.1f,-8866.45f,-88413.1f,-92497.2f,-8920.72f,-87767f,-92508.6f,-8866.45f,-88046.9f,-92182.7f,-8061.98f,-88133.2f,-92823.1f,-8007.72f,-88413.1f,-92497.2f,-8920.72f,-88133.2f,-92823.1f,-8866.45f,-88413.1f,-92497.2f,-8920.72f,-88133.2f,-92823.1f,-8007.72f,-88413.1f,-92497.2f,-8061.98f,-89615.9f,-94096.6f,-8007.72f,-89895.8f,-93770.7f,-8061.98f,-88133.2f,-92823.1f,-8007.72f,-88413.1f,-92497.2f,-8920.72f,-88133.2f,-92823.1f,-8920.72f,-89596.5f,-94079.9f,-8061.98f,-88133.2f,-92823.1f,-8061.98f,-89615.9f,-94096.6f,-8061.98f,-88133.2f,-92823.1f,-8920.72f,-89596.5f,-94079.9f,-7298.12f,-93491.8f,-81123.9f,-6464.54f,-93458.9f,-81162.2f,-7298.12f,-2550.94f,-3019.36f,-6464.54f,-2518.03f,-3057.67f,-7298.12f,-2550.94f,-3019.36f,-6464.54f,-93458.9f,-81162.2f,6456.25f,-40240.8f,-15469.8f,6179.01f,-102925f,-68042.7f,6178.41f,-102089f,-68973.2f,6276.06f,-41291.8f,-14246f,6179.01f,-102925f,-68042.7f,6179.01f,-102925f,-68042.7f,6276.06f,-40907.1f,-14694f,6179.01f,-102925f,-68042.7f,6276.06f,-41713.9f,-13886.7f,6269.01f,-103571f,-67018.6f,6022.45f,-21752.5f,23.5976f,6022.45f,-26787.1f,-4300.36f,10735.6f,-26787.1f,-4300.36f,10735.6f,-21752.5f,23.5976f,6178.41f,-102089f,-68973.2f,6178.41f,-102089f,-68973.2f,6022.45f,-101057f,-70411.1f
};
public String objectName;
public int triangleCount;
public int verticeCount;
public float[] vertices;
public float[] normals;
public float[] textures;
public short[] indices;
public float[] matrices;
public float[] pivots;
public float[] animations;
public void awake() {
ByteBuffer vbb = ByteBuffer.allocateDirect(verticeTest.length * 4);
vbb.order(ByteOrder.nativeOrder());
mVertexBuffer = vbb.asFloatBuffer();
mVertexBuffer.put(verticeTest);
mVertexBuffer.position(0);
ByteBuffer tbb = ByteBuffer.allocateDirect(textures.length * 4);
tbb.order(ByteOrder.nativeOrder());
mTextureBuffer = tbb.asFloatBuffer();
mTextureBuffer.put(textures);
mTextureBuffer.position(0);
//short has 2 bytes
ByteBuffer ibb = ByteBuffer.allocateDirect(indicesTest.length*2);
ibb.order(ByteOrder.nativeOrder());
indexBuffer = ibb.asShortBuffer();
indexBuffer.put(indicesTest);
indexBuffer.position(0);
verticeCount = (triangleCount*3);
}
public void draw(GL10 gl) {
System.out.println("Draw Method Called in Object");
gl.glEnable(GL10.GL_TEXTURE_2D); //workaround bug 3623
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, mVertexBuffer);
System.out.println("Triangle Vertice Count is "+verticeCount);
int x = vertices.length;
System.out.println("Rendering following number of vertices "+x);
int y = indices.length;
System.out.println("Rendering following number of indices "+y);
gl.glDrawElements(GL10.GL_TRIANGLES, indices.length, GL10.GL_UNSIGNED_SHORT, indexBuffer);
}
}
And here is the code where I call the draw method :
import java.nio.FloatBuffer;
import java.util.ArrayList;
import java.util.Iterator;
import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;
import android.content.Context;
import android.opengl.GLSurfaceView;
import android.opengl.GLU;
class GLRenderer implements GLSurfaceView.Renderer {
private static final String TAG = "GLRenderer";
private final Context context;
private final GLCube cube = new GLCube();
private long startTime;
private long fpsStartTime;
private long numFrames;
SceneObject drawObject;
SceneObject object;
//Used for object position and rotation.
float zRotation;
float xRotation;
float yRotation;
float kxRotation = 0.0f;
float kyRotation = 0.0f;
ArrayList<SceneObject> sceneObjects = new ArrayList<SceneObject>();
boolean SEE_THRU = false;
GLRenderer(Context context) {
this.context = context;
}
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
// Setup any OpenGL Options that are required.
gl.glEnable(GL10.GL_DEPTH_TEST);
gl.glDepthFunc(GL10.GL_LEQUAL);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
gl.glEnable(GL10.GL_TEXTURE_2D);
if (SEE_THRU) {
gl.glDisable(GL10.GL_DEPTH_TEST);
gl.glEnable(GL10.GL_BLEND);
gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_ONE);
}
//Optional - disable dither to boost peformance.
//gl.glDisable(GL10.GL_DITHER); //Dithering enabled by default.
//Turn on the lights.
float lightAmbient[] = new float[] { 0.2f, 0.2f, 0.2f, 1};
float lightDiffuse[] = new float[] {1, 1, 1, 1};
float[] lightPos = new float[] {1 ,1 ,1 , 1};
gl.glEnable(GL10.GL_LIGHTING);
gl.glEnable(GL10.GL_LIGHT0);
gl.glLightfv(GL10.GL_LIGHT0, GL10.GL_AMBIENT, lightAmbient, 0);
gl.glLightfv(GL10.GL_LIGHT0, GL10.GL_DIFFUSE, lightDiffuse, 0);
gl.glLightfv(GL10.GL_LIGHT0, GL10.GL_POSITION, lightPos, 0);
//Specify which materials we should use.
float matAmbient[] = new float[] {1, 1, 1, 1};
float matDiffuse[] = new float[] {1, 1, 1, 1};
gl.glMaterialfv(GL10.GL_FRONT_AND_BACK, GL10.GL_AMBIENT, matAmbient, 0);
gl.glMaterialfv(GL10.GL_FRONT_AND_BACK, GL10.GL_DIFFUSE, matDiffuse, 0);
}
public void onSurfaceChanged(GL10 gl, int width, int height) {
//Define the view frustrum
gl.glViewport(0, 0, width, height);
gl.glMatrixMode(GL10.GL_PROJECTION);
float ratio = (float)width/height;
gl.glLoadIdentity();
//gl.glOrthof(0, 480f, 800f, 0, 0, 1);
GLU.gluPerspective(gl, 45.0f, ratio, 1.0f, 100f);
}
public void onDrawFrame (GL10 gl) {
//Defs for rotation of object.
float kzRotation = 0.0f;
kyRotation +=1.0f;
kxRotation =280.0f;
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
SceneObject object = sceneObjects.get(13); //Get the object
//Position the model.
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
gl.glTranslatef(0.0f, 0.0f, -30.0f);
gl.glScalef(0.0001f, 0.0001f, 0.0001f);
zRotation = kzRotation;
xRotation = kxRotation;
yRotation = kyRotation;
gl.glRotatef(yRotation, 0.0f, 1.0f, 0.0f);
gl.glRotatef(xRotation, 1.0f, 0.0f, 0.0f);
gl.glRotatef(zRotation, 0.0f, 0.0f, 1.0f);
object.draw(gl);
}
}
}
The problem is that the object is not displaying as it should, but instead looks warped and squashed. Can anyone spot what might be wrong ?
EDIT – Changed the onSufaceChanged method as per Tim’s answer below, however no improvement.
I’ve added an image of how the object is rendering on Android and the same object rendering correct on the iPhone. The most noticeable problem is that the “legs” should be straight and not bend and overall the object should be much longer. I’m sure the vertices and indices in the code above are correct (they are exactly the same as the iPhone ones).
In case it is relevant here is how I am setting up the surfaceview / view:
public class SaxParserActivity extends Activity {
/** Called when the activity is first created. */
ArrayList<SceneObject> sceneObjects = new ArrayList<SceneObject>();
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//setContentView(R.layout.main);
GLView view;
view = new GLView(this, sceneObjects);
//Pass down our sceneObjects into the view class.
//view.sceneObjects = sceneObjects;
setContentView(view);
}
}
class GLView extends GLSurfaceView {
private final GLRenderer renderer;
ArrayList<SceneObject> sceneObjects = new ArrayList<SceneObject>();
GLView(Context context, ArrayList<SceneObject> sceneObjects) {
super (context);
//Uncomment this to turn on error-checking and logging.
//setDebugFlags(DEBUG_CHECK_GL_ERROR | DEBUG_LOG_GL_CALLS);
renderer = new GLRenderer(context);
//Pass down our sceneObjects.
renderer.sceneObjects = sceneObjects;
setRenderer(renderer);
}
}
I’m a bit confused by what you’re doing. Why do you wipe on the projection matrix in
onDrawFrame, after setting it inonSurfaceChanged?You should set projection in onSurfaceChanged like so:
And then change back to modelview and don’t disturb the projection matrix during
onDrawFrame.You’ll probably need to recalibrate your scale and translate in
onDrawFrameas well after doing this.