Related
I am trying to draw lines connected to each other. Let's say they are creating a
rectangle. At each corner also I have points. When I have tested code in my
Samsung Galaxy Note 4 after several rotations, using touch, all rectangle ended up
with a single point at the center. I could not figure out why this was happening.
Code works fine in emulator. Also I am storing line and point data as array list
in my code. These array lists are used to create line and point object classes to
render.
public class GLRender implements GLSurfaceView.Renderer {
private final float[] mMVPMatrix = new float[16];
private final float[] mProjectionMatrix = new float[16];
private final float[] mViewMatrix = new float[16];
private float[] mRotationMatrix = new float[16];
private float[] mVRMatrix = new float[16];
private static ArrayList<Line> DrLine = new ArrayList<Line>();
private static ArrayList<Point> DrPoint = new ArrayList<Point>();
private float ratio;
private float Joint1;
private float Joint2;
private float x1, y1, z1, x2, y2, z2;
private float px, py, pz, ps;
private float[] nearN = new float[4];
private static ArrayList<ArrayList<String>> LineArray = new ArrayList<ArrayList<String>>();
private ArrayList<String> L = new ArrayList<String>();
private ArrayList<String> P = new ArrayList<String>();
private static ArrayList<ArrayList<String>> PointArray = new ArrayList<ArrayList<String>>();
private static ArrayList<String> EmptyLine = new ArrayList<String>();
private static ArrayList<String> EmptyPoint = new ArrayList<String>();
private static ArrayList<ArrayList<ArrayList<String>>> UndoL = new ArrayList<ArrayList<ArrayList<String>>>();
private static ArrayList<ArrayList<ArrayList<String>>> UndoP = new ArrayList<ArrayList<ArrayList<String>>>();
public GLRender(Activity activity) {
}
public void onSurfaceCreated(GL10 unused, EGLConfig config) {
// Set the background frame color
//GLES20.glClearColor(0.53f, 0.53f, 0.53f, 1.0f);
GLES20.glClearColor(0.474f, 0.537f, 0.078f, 1.0f);
}
public void onDrawFrame(GL10 unused) {
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT);
Drawer();
Line XLine = new Line();
XLine.SetVerts(0.0f, 0.0f, 0.0f, 1.0f / 10, 0.0f, 0.0f);
XLine.SetColor(1.0f, 0.0f, 0.0f, 1.0f);
Line YLine = new Line();
YLine.SetVerts(0.0f, 0.0f, 0.0f, 0.0f, 1.0f / 10, 0.0f);
YLine.SetColor(0.0f, 1.0f, 0.0f, 1.0f);
Line ZLine = new Line();
ZLine.SetVerts(0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f / 10);
ZLine.SetColor(0.0f, 0.0f, 1.0f, 1.0f);
Matrix.setIdentityM(mViewMatrix, 0);
Matrix.setLookAtM(mViewMatrix, 0, 0, 0, 1.0f , 0f, 0f, 0f, 0f, 1.0f, 0.0f);
Matrix.setIdentityM(mRotationMatrix, 0);
Matrix.rotateM(mRotationMatrix, 0, mXAngle, 0, 1f, 0);
Matrix.rotateM(mRotationMatrix, 0, mYAngle, 1f, 0, 0);
Matrix.setIdentityM(mVRMatrix, 0);
Matrix.multiplyMM(mVRMatrix, 0, mViewMatrix, 0, mRotationMatrix, 0);
Matrix.setIdentityM(mMVPMatrix, 0);
Matrix.multiplyMM(mMVPMatrix, 0, mProjectionMatrix, 0, mVRMatrix, 0);
Matrix.scaleM(mMVPMatrix,0,mScale,mScale,mScale);
if (DrLine.size() > 0) {
for (Line LineX : DrLine) {
LineX.draw(mMVPMatrix);
}
}
if (DrPoint.size() > 0) {
for (Point PointX : DrPoint) {
PointX.draw(mMVPMatrix);
}
}
XLine.draw(mMVPMatrix);
YLine.draw(mMVPMatrix);
ZLine.draw(mMVPMatrix);
}
public void onSurfaceChanged(GL10 unused, int width, int height) {
GLES20.glViewport(0, 0, width, height);
ratio = (float) width / height;
//Matrix.frustumM(mProjectionMatrix, 0, -ratio*10, ratio*10, -10, 10, 1, 9);
Matrix.orthoM(mProjectionMatrix, 0, -ratio, ratio, -1.0f, 1.0f, -5.0f, 5.0f);
}
public static int loadShader(int type, String shaderCode){
// create a vertex shader type (GLES20.GL_VERTEX_SHADER)
// or a fragment shader type (GLES20.GL_FRAGMENT_SHADER)
int shader = GLES20.glCreateShader(type);
// add the source code to the shader and compile it
GLES20.glShaderSource(shader, shaderCode);
GLES20.glCompileShader(shader);
return shader;
}
private Float TempMaxPointHolder = 0.0f;
private Float MaxPointHolder = 0.0f;
public Float Scaler(){
Float TempScaler = 1.0f;
Iterator<ArrayList<String>> MaxPointFinder = PointArray.iterator();
while (MaxPointFinder.hasNext()){
ArrayList<String> MaxPoint = MaxPointFinder.next();
TempMaxPointHolder = Math.abs(Math.max(Math.max(Float.parseFloat(MaxPoint.get(1)),Float.parseFloat(MaxPoint.get(2))),Float.parseFloat(MaxPoint.get(3))));
if (TempMaxPointHolder > MaxPointHolder){
MaxPointHolder = TempMaxPointHolder;
}
}
TempScaler = 0.9f / MaxPointHolder;
return TempScaler;
}
public void Drawer(){
Float Scaler = Scaler();
Integer Lindex = 0;
ArrayList<Point> TempDrPoint = new ArrayList<Point>();
ArrayList<Line> TempDrLine = new ArrayList<Line>();
Iterator<ArrayList<String>> Litr = LineArray.iterator();
while (Litr.hasNext()) {
L = Litr.next();
Joint1 = Float.parseFloat(L.get(1));
Joint2 = Float.parseFloat(L.get(2));
Iterator<ArrayList<String>> PitrL = PointArray.iterator();
while (PitrL.hasNext()){
P = PitrL.next();
if (Float.parseFloat(P.get(0)) == Joint1) {
x1 = Float.parseFloat(P.get(1)) * Scaler;
y1 = Float.parseFloat(P.get(2)) * Scaler;
z1 = Float.parseFloat(P.get(3)) * Scaler;
}
if (Float.parseFloat(P.get(0)) == Joint2) {
x2 = Float.parseFloat(P.get(1)) * Scaler;
y2 = Float.parseFloat(P.get(2)) * Scaler;
z2 = Float.parseFloat(P.get(3)) * Scaler;
}
}
Line TempLine = new Line();
TempLine.SetVerts(x1, y1, z1, x2, y2, z2);
if (L.get(3) == "0") {
TempLine.SetColor(0.0f, 0.0f, 0.0f, 1.0f);
}
else if (L.get(3) == "1"){
TempLine.SetColor(0.66f, 0.73f, 0.21f, 1.0f);
}
TempDrLine.add(TempLine);
Lindex = Lindex + 1;
}
setDrLine(TempDrLine);
Integer Pindex = 0;
Iterator<ArrayList<String>> Pitr = PointArray.iterator();
while (Pitr.hasNext()){
P = Pitr.next();
px = Float.parseFloat(P.get(1)) * Scaler;
py = Float.parseFloat(P.get(2)) * Scaler;
pz = Float.parseFloat(P.get(3)) * Scaler;
ps = Float.parseFloat(P.get(4));
Point TempPoint = new Point();
TempPoint.SetPointVerts(px, py, pz);
if (ps == 0.0f) {
TempPoint.SetPointColor(0.65f, 0.37f, 0.11f, 1.0f);
}
else if (ps == 1.0f) {
TempPoint.SetPointColor(0.68f, 0.07f, 0.32f, 1.0f);
}
TempDrPoint.add(TempPoint);
Pindex = Pindex + 1;
}
setDrPoint(TempDrPoint);
}
public volatile float mXAngle;
public volatile float mYAngle;
public ArrayList<Line> getDrLine() {
return DrLine;
}
public ArrayList<Point> getDrPoint(){
return DrPoint;
}
public void setDrLine(ArrayList<Line> XDrLine) {
DrLine = XDrLine;
}
public void setDrPoint(ArrayList<Point> XDrPoint) {
DrPoint = XDrPoint;
}
public float getXAngle() {
return mXAngle;
}
public float getYAngle(){
return mYAngle;
}
public void setAngleX(float Xangle) {
mXAngle = Xangle;
}
public void setAngleY(float Yangle) {
mYAngle = Yangle;
}
public volatile float mScale = 1;
public volatile float mXFocus;
public volatile float mYFocus;
public void setZoom(float scale){
mScale = scale;
}
public void setFocus(float XFocus, float YFocus){
mXFocus = XFocus;
mYFocus = YFocus;
}
public float getmScale(){
return mScale;
}
public float getmXFocus(){
return mXFocus;
}
public float getmYFocus(){
return mYFocus;
}
public void setLineArray(ArrayList<ArrayList<String>> XLine){
LineArray = XLine;
}
public ArrayList<ArrayList<String>> getLineArray(){
return LineArray;
}
public void setUndoL(ArrayList<ArrayList<String>> UndoLine){
this.UndoL.add(new ArrayList<ArrayList<String>>(UndoLine));
}
public ArrayList<ArrayList<ArrayList<String>>> getUndoL() {
return UndoL;
}
public void setUndoP(ArrayList<ArrayList<String>> UndoPoint){
this.UndoP.add(new ArrayList<ArrayList<String>>(UndoPoint));
}
public ArrayList<ArrayList<ArrayList<String>>> getUndoP() {
return UndoP;
}
public void setPointArray(ArrayList<ArrayList<String>> XPoint){
PointArray = XPoint;
}
public ArrayList<ArrayList<String>> getPointArray(){
return PointArray;
}
gives error contents_sample_state: [ agr({[3 ,38]=11, [3 ,7 ,38]=28}) ]
public class Line {
private FloatBuffer VertexBuffer;
private final String VertexShaderCode =
// This matrix member variable provides a hook to manipulate
// the coordinates of the objects that use this vertex shader
"uniform mat4 uMVPMatrix;" +
"attribute vec4 vPosition;" +
"void main() {" +
// the matrix must be included as a modifier of gl_Position
" gl_Position = uMVPMatrix * vPosition;" +
"}";
private final String FragmentShaderCode =
"precision mediump float;" +
"uniform vec4 vColor;" +
"void main() {" +
" gl_FragColor = vColor;" +
"}";
protected int GlProgram;
protected int PositionHandle;
protected int ColorHandle;
protected int MVPMatrixHandle;
// number of coordinates per vertex in this array
static final int COORDS_PER_VERTEX = 3;
static float LineCoords[] = {
0.0f, 0.0f, 0.0f,
1.0f, 0.0f, 0.0f
};
private final int VertexCount = LineCoords.length / COORDS_PER_VERTEX;
private final int VertexStride = COORDS_PER_VERTEX * 4; // 4 bytes per vertex
// Set color with red, green, blue and alpha (opacity) values
float color[] = { 0.0f, 0.0f, 0.0f, 1.0f };
public Line() {
// initialize vertex byte buffer for shape coordinates
ByteBuffer bb = ByteBuffer.allocateDirect(
// (number of coordinate values * 4 bytes per float)
LineCoords.length * 4);
// use the device hardware's native byte order
bb.order(ByteOrder.nativeOrder());
// create a floating point buffer from the ByteBuffer
VertexBuffer = bb.asFloatBuffer();
// add the coordinates to the FloatBuffer
VertexBuffer.put(LineCoords);
// set the buffer to read the first coordinate
VertexBuffer.position(0);
int vertexShader = GLRender.loadShader(GLES20.GL_VERTEX_SHADER, VertexShaderCode);
int fragmentShader = GLRender.loadShader(GLES20.GL_FRAGMENT_SHADER, FragmentShaderCode);
GlProgram = GLES20.glCreateProgram(); // create empty OpenGL ES Program
GLES20.glAttachShader(GlProgram, vertexShader); // add the vertex shader to program
GLES20.glAttachShader(GlProgram, fragmentShader); // add the fragment shader to program
GLES20.glLinkProgram(GlProgram); // creates OpenGL ES program executables
}
public void SetVerts(float v0, float v1, float v2, float v3, float v4, float v5) {
LineCoords[0] = v0;
LineCoords[1] = v1;
LineCoords[2] = v2;
LineCoords[3] = v3;
LineCoords[4] = v4;
LineCoords[5] = v5;
VertexBuffer.put(LineCoords);
// set the buffer to read the first coordinate
VertexBuffer.position(0);
}
public void SetColor(float red, float green, float blue, float alpha) {
color[0] = red;
color[1] = green;
color[2] = blue;
color[3] = alpha;
}
public void draw(float[] mvpMatrix) {
// Add program to OpenGL ES environment
GLES20.glUseProgram(GlProgram);
// get handle to vertex shader's vPosition member
PositionHandle = GLES20.glGetAttribLocation(GlProgram, "vPosition");
// Enable a handle to the triangle vertices
GLES20.glEnableVertexAttribArray(PositionHandle);
// Prepare the triangle coordinate data
GLES20.glVertexAttribPointer(PositionHandle, COORDS_PER_VERTEX,
GLES20.GL_FLOAT, false,
VertexStride, VertexBuffer);
// get handle to fragment shader's vColor member
ColorHandle = GLES20.glGetUniformLocation(GlProgram, "vColor");
// Set color for drawing the triangle
GLES20.glUniform4fv(ColorHandle, 1, color, 0);
// get handle to shape's transformation matrix
MVPMatrixHandle = GLES20.glGetUniformLocation(GlProgram, "uMVPMatrix");
//GLRender.checkGlError("glGetUniformLocation");
// Apply the projection and view transformation
GLES20.glUniformMatrix4fv(MVPMatrixHandle, 1, false, mvpMatrix, 0);
//GLRender.checkGlError("glUniformMatrix4fv");
GLES20.glLineWidth(5);
// Draw the triangle
GLES20.glDrawArrays(GLES20.GL_LINES, 0, VertexCount);
// Disable vertex array
GLES20.glDisableVertexAttribArray(PositionHandle);
}
}
public class GLSurface extends GLSurfaceView {
//public static GLRender xRender;
ScaleGestureDetector ScaleDetect;
MainActivity mMain;
OpenGL XOPL = mMain.xOpenGL;
public GLSurface(Context context, AttributeSet attrs){
super(context, attrs);
// Render the view only when there is a change in the drawing data
//setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);
ScaleDetect = new ScaleGestureDetector(context, new ScaleDetectorListener());
}
private float mPreviousX;
private float mPreviousY;
float density = this.getResources().getDisplayMetrics().density;
private static final int MAX_CLICK_DURATION = 300;
private long pressStartTime;
#Override
public boolean onTouchEvent(MotionEvent e) {
ScaleDetect.onTouchEvent(e);
float x = e.getX();
float y = e.getY();
switch (e.getAction()) {
case MotionEvent.ACTION_MOVE:
if(!ScaleDetect.isInProgress()) {
float xMoveRange = x - mPreviousX;
float yMoveRange = y - mPreviousY;
float dx = 0.0f;
float dy = 0.0f;
float w = this.getWidth();
float h = this.getHeight();
if (Math.abs(xMoveRange) > w / 100 && Math.abs(yMoveRange) < h / 100){
dx = xMoveRange / density / 2.0f;
XOPL.xRender.setAngleX(XOPL.xRender.getXAngle() + dx);
}
if (Math.abs(xMoveRange) < w / 100 && Math.abs(yMoveRange) > h / 100){
dy = yMoveRange / density / 2.0f;
XOPL.xRender.setAngleY(XOPL.xRender.getYAngle() + dy);
}
XOPL.myGLView.requestRender();
}
break;
case MotionEvent.ACTION_DOWN:
pressStartTime = System.currentTimeMillis();
break;
case MotionEvent.ACTION_UP:
long pressDuration = System.currentTimeMillis() - pressStartTime;
if (pressDuration < MAX_CLICK_DURATION) {
float Nx = (x - Float.parseFloat(Double.toString(this.getWidth())) * 0.5f) / (Float.parseFloat(Double.toString(this.getWidth())) * 0.5f);
float Ny = (y - Float.parseFloat(Double.toString(this.getHeight())) * 0.5f) / (Float.parseFloat(Double.toString(this.getHeight())) * 0.5f);
float Nz = 1.0f;
XOPL.xRender.setNCoordinate(Nx, Ny, Nz);
XOPL.xRender.Selection();
XOPL.myGLView.requestRender();
}
break;
}
mPreviousX = x;
mPreviousY = y;
return true;
}
private float sizeCoef = 1;
public class ScaleDetectorListener extends ScaleGestureDetector.SimpleOnScaleGestureListener {
float scaleFocusX = 0;
float scaleFocusY = 0;
public boolean onScale(ScaleGestureDetector arg0) {
float scale = arg0.getScaleFactor() * sizeCoef;
sizeCoef = scale;
XOPL.xRender.setZoom(sizeCoef);
XOPL.myGLView.requestRender();
return true;
}
public boolean onScaleBegin(ScaleGestureDetector arg0) {
invalidate();
scaleFocusX = arg0.getFocusX();
scaleFocusY = arg0.getFocusY();
XOPL.xRender.setFocus(scaleFocusX,scaleFocusY);
return true;
}
public void onScaleEnd(ScaleGestureDetector arg0) {
scaleFocusX = 0;
scaleFocusY = 0;
XOPL.xRender.setFocus(scaleFocusX,scaleFocusY);
}
}
}
Not sure if this is the problem, but watch out for things like:
XOPL.xRender.setAngleX(XOPL.xRender.getXAngle() + dx)
... especially when using mediump precision in shaders. Generally I'd recommend changing setAngle functions to exploit rotational symmetry and wrap the value around so you get an absolute range used at the API-level of of +-Pi.
In your current code if the user keeps swiping in one direction, eventually you'll run our of bits and everything will either stop rotating (at best), or fail with infinities or NaN results (at worst).
Note using "-Pi to +Pi" is preferred to using "0 to +2Pi", because the sign-bit is free in most floating point representations so preserves more dynamic precision.
Example code:
public float wrapRadians(float angle) {
// If angle is negative ensure value is higher than minus pi
if (angle < 0) {
while (angle < -math.PI) {
angle += 2 * math.PI;
}
// Else angle is positive so ensure value is less than pi
} else {
while (angle > math.PI) {
angle -= 2 * math.PI;
}
}
return angle;
}
public float setXAngle(float XAngle) {
mXAngle = wrapRadians(XAngle);
}
public float setYAngle(float YAngle) {
mYAngle = wrapRadians(YAngle);
}
I've a 3d-model in OpenGL ES in Android. I've already implemented swipe-gestures for translating, rotating and zooming into the model. Everything but the zooming works fine. I'm not sure what I'm missing or what I have to change but I'm not able to zoom into my model.
The model is a building. What I'd like to do is to zoom into the different floors of the building. But no matter how I change my implementation, I'm not able to do this.
Either the building disappears when I zoom in or the zoom has a limitation so that I can't zoom into it further....
First of all I decreased the field of view by modifying the Matrix:
frustumM(matrix, 0, -ratio/zoom, ratio/zoom, -1/zoom, 1/zoom, nearPlane, farPlane).
Someone told me, that this is not the correct approach and I should modify the eyeZ value like:
eyeZ = -1.0/zoom
The first approach is working, but I'd like to know what my mistake with the second approach is, because it has the issues I mentioned in the beginning.
My renderer-class is the following:
public class MyGLRenderer implements GLSurfaceView.Renderer {
private float[] mModelMatrix = new float[16];
private final float[] mMVMatrix = new float[16];
private final float[] mProjectionMatrix = new float[16];
private final float[] mViewMatrix = new float[16];
private float nearPlaneDistance = 1f;
private float farPlaneDistance = 200f;
private float modelRatio = 1.0f;
private int offset = 0;
private float eyeX = 0;
private float eyeY = 0;
private float eyeZ = -1;
private float centerX = 0f;
private float centerY = 0f;
private float centerZ = 0f;
private float upX = 0f;
private float upY = 1.0f;
private float upZ = 0.0f;
private float mZoomLevel = 1f;
private float defaultRotationX = 100.0f; //building otherwise on the wrong side
private float defaultRotationZ = 180.0f; //building otherwise on the wrong side
private float rotationX = defaultRotationX;
private float rotationY = 0.0f;
private float rotationZ = defaultRotationZ;
private float translateX = 0.0f;
private float translateY = 0.0f;
private float translateZ = 0.0f;
private float scaleFactor = 20.0f; //no matter what scale factor -> it's not possible to zoom into the building...
private float ratio;
private float width;
private float height;
private List<IDrawableObject> drawableObjects;
public Model3D model3d;
public MyGLRenderer(Model3D model3d) {
this.model3d = model3d;
getModelScale();
}
private void getModelScale() {
float highestValue = (model3d.width > model3d.height) ? model3d.width
: model3d.height;
modelRatio = 2f / highestValue;
}
#Override
public void onSurfaceCreated(GL10 unused, EGLConfig config) {
// Set the background frame color
GLES20.glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
GLES20.glDisable(GLES20.GL_CULL_FACE);
GLES20.glEnable(GLES20.GL_DEPTH_TEST);
drawableObjects = ... ; //to much detail, basically getting triangles
}
#Override
public void onDrawFrame(GL10 unused) {
float[] mMVPMatrix = new float[16];
// Draw background color
Matrix.setIdentityM(mModelMatrix, 0);
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT);
// model is in origin-solution too big
Matrix.scaleM(mModelMatrix, 0, modelRatio * scaleFactor, modelRatio
* scaleFactor, modelRatio * scaleFactor);
Matrix.translateM(mModelMatrix, 0, translateX, translateY, translateZ);
rotateModel(mModelMatrix, rotationX, rotationY, rotationZ, true);
// Set the camera position (View matrix)
Matrix.setLookAtM(mViewMatrix, offset, eyeX, eyeY, eyeZ / mZoomLevel,
centerX, centerY, centerZ, upX, upY, upZ);
// combine the model with the view matrix
Matrix.multiplyMM(mMVMatrix, 0, mViewMatrix, 0, mModelMatrix, 0);
// this projection matrix is applied to object coordinates
// in the onDrawFrame() method
Matrix.frustumM(mProjectionMatrix, 0, -ratio, ratio, 1, -1,
nearPlaneDistance, farPlaneDistance);
// Calculate the projection and view transformation
Matrix.multiplyMM(mMVPMatrix, 0, mProjectionMatrix, 0, mMVMatrix, 0);
for (IDrawableObject d : drawableObjects) {
d.draw(mMVPMatrix);
}
}
private void rotateModel(float[] mModelMatrix, Float x, Float y, Float z,
boolean rotateAroundCenter) {
// translation for rotating the model around its center
if (rotateAroundCenter) {
Matrix.translateM(mModelMatrix, 0, (model3d.width / 2f), 0,
(model3d.height / 2f));
}
if (x != null) {
Matrix.rotateM(mModelMatrix, 0, x, 1.0f, 0.0f, 0.0f);
}
if (y != null) {
Matrix.rotateM(mModelMatrix, 0, y, 0.0f, 1.0f, 0.0f);
}
if (z != null) {
Matrix.rotateM(mModelMatrix, 0, z, 0.0f, 0.0f, 1.0f);
}
// translation back to the origin
if (rotateAroundCenter) {
Matrix.translateM(mModelMatrix, 0, -(model3d.width / 2f), 0,
-(model3d.height / 2f));
}
}
#Override
public void onSurfaceChanged(GL10 unused, int width, int height) {
// Adjust the viewport based on geometry changes,
// such as screen rotation
GLES20.glViewport(0, 0, width, height);
this.width = width;
this.height = height;
ratio = (float) width / height;
}
public static int loadShader(int type, String shaderCode) {
// create a vertex shader type (GLES20.GL_VERTEX_SHADER)
// or a fragment shader type (GLES20.GL_FRAGMENT_SHADER)
int shader = GLES20.glCreateShader(type);
// add the source code to the shader and compile it
GLES20.glShaderSource(shader, shaderCode);
GLES20.glCompileShader(shader);
return shader;
}
public int getFPS() {
return lastMFPS;
}
public static void checkGlError(String glOperation) {
int error;
while ((error = GLES20.glGetError()) != GLES20.GL_NO_ERROR) {
Log.e(TAG, glOperation + ": glError " + error);
throw new RuntimeException(glOperation + ": glError " + error);
}
}
public void setZoom(float zoom) {
this.mZoomLevel = zoom;
}
public void setDistance(float distance) {
eyeZ = distance;
}
public float getDistance() {
return eyeZ;
}
public float getRotationX() {
return rotationX;
}
public void setRotationX(float rotationX) {
this.rotationX = defaultRotationX + rotationX;
}
public float getRotationY() {
return rotationY;
}
public void setRotationY(float rotationY) {
this.rotationY = rotationY;
}
public float getRotationZ() {
return rotationZ;
}
public void setRotationZ(float rotationZ) {
this.rotationZ = defaultRotationZ + rotationZ;
}
public float getFarPlane() {
return farPlaneDistance;
}
public float getNearPlane() {
return nearPlaneDistance;
}
public void addTranslation(float mPosX, float mPosY) {
this.translateX = mPosX;
this.translateY = mPosY;
}
public void downPressed() {
translateX -= 10;
}
public void upPressed() {
translateX += 10;
}
public void actionMoved(float mPosX, float mPosY) {
float translationX = (mPosX / width);
float translationY = -(mPosY / height);
addTranslation(translationX, translationY);
}
public float getmZoomLevel() {
return mZoomLevel;
}
public void setmZoomLevel(float mZoomLevel) {
this.mZoomLevel = mZoomLevel;
}
public float getWidth() {
return width;
}
public float getHeight() {
return height;
}
public void setTranslation(Float x, Float y, Float z) {
if (x != null) {
this.translateX = -x;
}
if (y != null) {
this.translateY = y;
}
if (z != null) {
this.translateZ = -z;
}
}
public void setRotation(Float x, Float y, Float z) {
if (x != null) {
this.rotationX = defaultRotationX + x;
}
if (y != null) {
this.rotationY = y;
}
if (z != null) {
this.rotationZ = defaultRotationZ + z;
}
}
public void setScale(float scale) {
this.mZoomLevel = scale;
}
public float getDefaultRotationX() {
return defaultRotationX;
}
}
Do you see any mistake I'm currently doing? You can also have a look into the github repository: https://github.com/Dalanie/OpenGL-ES/tree/master/buildingGL
First you must define what you mean by "zoom". In the scenario of a perspective projection, there are a few possibilities:
You change the field of view. This is analogous to the zoom of cameras, where zooming results in changing the focal width.
You just scale the model before the projection.
You change the distance of the model (nearer to the camera to zoom in, farer away to zoom out)
The variant 1 is what you did by changing the frustum. In my opinion, that is the most intuitive effect. At least to someone who is used to cameras. ALso note that this has the same effect as upscaling some sub-rectangle of the 2d projected image to fill the whole screen.
Changing eyeZ is approach 3. But now you must be carefol to not move the object out of the viewing volume (which seems to be the issue you are describing). Ideally you would modify the frustum here, too. But to keep the field of view, while moving the near/far planes so that the object always stays inbetween. Note that this requires changing all 6 values of the frustum, what stays the same should be the ratios left/near, right/near, top/near and bottom/near to keep the FOV/aspect you had before.
I am creating a bar graph in android using opengl
from an activity I'm calling the renderer and from the renderer I'm calling a cube(im using cubes for showing the bars)
Here is my renderer code:
public class BarRenderer implements Renderer {
int[] vals;
private float translatex, translatez, scaly;
public BarRenderer(boolean useTranslucentBackground, int[] vals) {
mTranslucentBackground = useTranslucentBackground;
this.vals = vals;
for (int i = 0; i < this.vals.length; i++) {
mcube[i] = new Cube();
}
}
public void onDrawFrame(GL10 gl) {
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
gl.glClearColor(0.0f, 0.5f, 0.5f, 1.0f);
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
translatex = 0.5f;
scaly = 0.8f;
for (int i = 0; i < vals.length; i++) {
gl.glTranslatef((-1.0f + (translatex * i)), 0.0f, translatez);
gl.glRotatef(mAngle, 0.0f, 1.0f, 0.0f);
gl.glScalef(0.4f, scaly * vals[i], 0.6f);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_COLOR_ARRAY);
mcube[i].draw(gl);
}
mTransY = .075f;
mAngle = -60.0f;
translatez = -7.0f;
Log.i("Draw", "called");
}
public void onSurfaceChanged(GL10 gl, int width, int height) {
gl.glViewport(0, 0, width, height);
float aspectRatio;
float zNear = .1f;
float zFar = 1000;
float fieldOfView = 80.0f / 57.3f;
float size;
gl.glEnable(GL10.GL_NORMALIZE);
aspectRatio = (float) width / (float) height;
gl.glMatrixMode(GL10.GL_PROJECTION);
size = zNear * (float) (Math.tan((double) (fieldOfView / 2.0f)));
gl.glFrustumf(-size, size, -size / aspectRatio, size / aspectRatio,
zNear, zFar);
gl.glMatrixMode(GL10.GL_MODELVIEW);
}
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
gl.glDisable(GL10.GL_DITHER);
gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_FASTEST);
if (mTranslucentBackground) {
gl.glClearColor(0, 0, 0, 0);
} else {
gl.glClearColor(1, 1, 1, 1);
}
gl.glEnable(GL10.GL_CULL_FACE);
gl.glShadeModel(GL10.GL_SMOOTH);
gl.glEnable(GL10.GL_POINT_SMOOTH);
gl.glEnable(GL10.GL_DEPTH_TEST);
}
private boolean mTranslucentBackground;
private Cube[] mcube = new Cube[4];
private float mTransY;
private float mAngle;
}
but unfortunately it is giving the bar graph like this:
anyone will understand this is not exactly like a bar graph
but please point out my faults here, where am i doing wrong:
1>the bar heights are 4 1 2 1 but they r not accurately of their sizes
2>the space between the bars are supposed to be .5f apart but they start with a big gap but reduce repeatedly after every bar
3>how to start them from one base plane
EDIT:
4> can I animate the growth of this bars?how to do that
My cube code:
public class Cube {
private ByteBuffer mTfan1;
private ByteBuffer mTfan2;
private int bar;
public Cube(int i) {
this.bar = i;
float vertices[] = {
-1.0f, 1.0f, 1.0f,
1.0f, 1.0f, 1.0f,
1.0f, -1.0f,1.0f,
-1.0f, -1.0f, 1.0f,
-1.0f, 1.0f, -1.0f,
1.0f, 1.0f, -1.0f,
1.0f, -1.0f, -1.0f,
-1.0f, -1.0f, -1.0f
};
byte maxColor = (byte) 255;
byte colors[][] =
{
{maxColor,maxColor, 0,maxColor},
{0, maxColor,maxColor,maxColor},
{0, 0, 0,maxColor},
{maxColor, 0,maxColor,maxColor},
{maxColor, 0, 0,maxColor},
{0, maxColor, 0,maxColor},
{0, 0,maxColor,maxColor},
{0, 0, 0,maxColor}
};
byte tfan1[] =
{
1,0,3,
1,3,2,
1,2,6,
1,6,5,
1,5,4,
1,4,0
};
byte tfan2[] =
{
7,4,5,
7,5,6,
7,6,2,
7,2,3,
7,3,0,
7,0,4
};
byte indices[] =
{ 0, 3, 1, 0, 2, 3 };
ByteBuffer vbb = ByteBuffer.allocateDirect(vertices.length * 4);
vbb.order(ByteOrder.nativeOrder());
mFVertexBuffer = vbb.asFloatBuffer();
mFVertexBuffer.put(vertices);
mFVertexBuffer.position(0);
mColorBuffer = ByteBuffer.allocateDirect(colors.length);
mColorBuffer.put(colors[bar]);
mColorBuffer.position(0);
mTfan1 = ByteBuffer.allocateDirect(tfan1.length);
mTfan1.put(tfan1);
mTfan1.position(0);
mTfan2 = ByteBuffer.allocateDirect(tfan2.length);
mTfan2.put(tfan2);
mTfan2.position(0);
}
public void draw(GL10 gl)
{
gl.glVertexPointer(3, GL11.GL_FLOAT, 0, mFVertexBuffer);
gl.glColorPointer(4, GL11.GL_UNSIGNED_BYTE, 0, mColorBuffer);
gl.glDrawElements( gl.GL_TRIANGLE_FAN, 6 * 3, gl.GL_UNSIGNED_BYTE, mTfan1);
gl.glDrawElements( gl.GL_TRIANGLE_FAN, 6 * 3, gl.GL_UNSIGNED_BYTE, mTfan2);
}
private FloatBuffer mFVertexBuffer;
private ByteBuffer mColorBuffer;
private ByteBuffer mIndexBuffer;
}
i think something has to be done in the draw method but what??how to animate here?
please help
thanks
2 Before glTranslate and rotate calls you should use glPushMatrix and after that glPopMatrix functions, or call glTranslate without increment. Because glTranslate multiply existing projection matrix on new matrix from glTranslate parameters
3
gl.glPushMatrix() ;
gl.glTranslate(0,y,0);
mcube[i].draw(gl);
gl.glPopMatrix();
with y= - Barheight/2 in your case or change vertex coordinates of your bars
I have done creating the 3d bar graph though I have some other issues right now
but I believe some one might be helpful with this code.
Myrenderer class:
public class BarRenderer implements GLSurfaceView.Renderer {
int[] vals;
private float translatex, scaly;
// For controlling cube's z-position, x and y angles and speeds (NEW)
float angleX = 0; // (NEW)
float angleY = 0; // (NEW)
float speedX = 0; // (NEW)
float speedY = 0; // (NEW)
float translatez;
public BarRenderer(Context context, boolean useTranslucentBackground,
int[] vals) {
mTranslucentBackground = useTranslucentBackground;
mfloor = new Cube(0);
mwall = new Cube(0);
this.vals = vals;
for (int i = 0; i < this.vals.length; i++) {
mcube[i] = new Cube(i);
}
}
public void onDrawFrame(GL10 gl) {
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
gl.glClearColor(0.0f, 0.5f, 0.5f, 1.0f);
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
translatex = 2.0f;
scaly = 0.8f;
for (int i = 0; i < vals.length; i++) {
gl.glPushMatrix();
mTransY = -5 + (scaly * vals[i]);
gl.glTranslatef((-3.0f + (translatex * i)), mTransY, translatez);
gl.glRotatef(mAngleX, 1.0f, 0.0f, 0.0f);
gl.glRotatef(mAngleY, 0.0f, 1.0f, 0.0f);
gl.glScalef(0.4f, scaly * vals[i], 0.4f);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_COLOR_ARRAY);
mcube[i].draw(gl);
gl.glPopMatrix();
}
mTransY = .075f;
// mAngleX = -90.0f;
// mAngleY = -0.01f;
mAngleX += speedX;
mAngleY += speedY;
translatez = -6.0f;
}
public void onSurfaceChanged(GL10 gl, int width, int height) {
gl.glViewport(0, 0, width, height);
float aspectRatio;
float zNear = .1f;
float zFar = 1000;
float fieldOfView = 80.0f / 57.3f;
float size;
gl.glEnable(GL10.GL_NORMALIZE);
aspectRatio = (float) width / (float) height;
gl.glMatrixMode(GL10.GL_PROJECTION);
size = zNear * (float) (Math.tan((double) (fieldOfView / 2.0f)));
gl.glFrustumf(-size, size, -size / aspectRatio, size / aspectRatio,
zNear, zFar);
gl.glMatrixMode(GL10.GL_MODELVIEW);
}
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
gl.glDisable(GL10.GL_DITHER);
gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_FASTEST);
if (mTranslucentBackground) {
gl.glClearColor(0, 0, 0, 0);
} else {
gl.glClearColor(1, 1, 1, 1);
}
gl.glEnable(GL10.GL_CULL_FACE);
gl.glShadeModel(GL10.GL_SMOOTH);
gl.glEnable(GL10.GL_POINT_SMOOTH);
gl.glEnable(GL10.GL_DEPTH_TEST);
}
private boolean mTranslucentBackground;
private Cube[] mcube = new Cube[4];
private Cube mfloor, mwall;
private float mTransY;
private float mAngleX,mAngleY;
}
and myGLsurfaceview class:
public class MyBarGLSurfaceView extends GLSurfaceView {
BarRenderer renderer; // Custom GL Renderer
// For touch event
private final float TOUCH_SCALE_FACTOR = 180.0f / 320.0f;
private float previousX;
private float previousY;
public MyBarGLSurfaceView(Context context,
boolean useTranslucentBackground, int[] vals) {
super(context);
renderer = new BarRenderer(context, useTranslucentBackground, vals);
this.setRenderer(renderer);
// Request focus, otherwise key/button won't react
this.requestFocus();
this.setFocusableInTouchMode(true);
}
// Handler for key event
#Override
public boolean onKeyUp(int keyCode, KeyEvent evt) {
switch (keyCode) {
case KeyEvent.KEYCODE_DPAD_LEFT: // Decrease Y-rotational speed
renderer.speedY -= 01.1f;
break;
case KeyEvent.KEYCODE_DPAD_RIGHT: // Increase Y-rotational speed
renderer.speedY += 01.1f;
break;
case KeyEvent.KEYCODE_DPAD_UP: // Decrease X-rotational speed
renderer.speedX -= 01.1f;
break;
case KeyEvent.KEYCODE_DPAD_DOWN: // Increase X-rotational speed
renderer.speedX += 01.1f;
break;
case KeyEvent.KEYCODE_A: // Zoom out (decrease z)
renderer.translatez -= 0.2f;
break;
case KeyEvent.KEYCODE_Z: // Zoom in (increase z)
renderer.translatez += 0.2f;
break;
}
return true; // Event handled
}
// Handler for touch event
#Override
public boolean onTouchEvent(final MotionEvent evt) {
float currentX = evt.getX();
float currentY = evt.getY();
float deltaX, deltaY;
switch (evt.getAction()) {
case MotionEvent.ACTION_MOVE:
// Modify rotational angles according to movement
deltaX = currentX - previousX;
deltaY = currentY - previousY;
renderer.angleX += deltaY * TOUCH_SCALE_FACTOR;
renderer.angleY += deltaX * TOUCH_SCALE_FACTOR;
}
// Save current x, y
previousX = currentX;
previousY = currentY;
return true; // Event handled
}
}
though it is done still I would like if anyone can please answer me
1> how to make this bar graphs to grow animatedly, right now when this bar graph activity starts the bar graph appears but i want the bar graph to grow animatedly not just show it
2> how to create a base and a background wall to the bar graph like this link http://www.fusioncharts.com/demos/gallery/#column-and-bar
3> and I was trying to rotate or move the bar graph as per user touch movements i tried the code like another example, you will see that code too and that is why i created this glsurfaceview class of my own, but for some reason it is not working, don't know where and what i have missed, if anyone have any idea please point it out to me
thanks
I am new to open GL, I just want to move a circle randomly in the screen , when the user touches the circle , I need to know the hit and miss.
this is what I'm able to achieve through the online classes.
render class:
public class HelloOpenGLES10Renderer implements Renderer {
private int points = 250;
private float vertices[] = { 0.0f, 0.0f, 0.0f };
private FloatBuffer vertBuff;
public float x = 0.0f, y = 0.0f;
public boolean color = false;
boolean first = true;
#Override
public void onDrawFrame(GL10 gl) {
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
gl.glTranslatef(x, y, 0);
gl.glColor4f(1.0f, 1.0f, 1.0f, 0f);
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertBuff);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDrawArrays(GL10.GL_TRIANGLE_FAN, 0, points);
}
#Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
Log.i("TAG", "change" + width + ":" + height);
gl.glViewport(0, 0, width, height);
float ratio = (float) width / height;
gl.glMatrixMode(GL10.GL_PROJECTION);
gl.glFrustumf(-ratio, ratio, -1, 1, 3, 7);
GLU.gluLookAt(gl, 0f, 0f, -5f, 0.0f, 0.0f, 0f, 0.0f, 1.0f, 0.0f);
}
#Override
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
Log.i("TAG", "CREATE");
gl.glClearColor(0.1f, 0.1f, 0.0f, 1.0f);
initShapes();
}
private void initShapes() {
vertices = new float[(points + 1) * 3];
for (int i = 3; i < (points + 1) * 3; i += 3) {
double rad = (i * 360 / points * 3) * (3.14 / 180);
vertices[i] = (float) Math.cos(rad) * 0.10f;
vertices[i + 1] = (float) Math.sin(rad) * 0.10f;
vertices[i + 2] = 0;
}
ByteBuffer bBuff = ByteBuffer.allocateDirect(vertices.length * 4);
bBuff.order(ByteOrder.nativeOrder());
vertBuff = bBuff.asFloatBuffer();
vertBuff.put(vertices);
vertBuff.position(0);
}
}
Activity:
package com.example.opengltrail;
import java.util.Random;
import android.app.Activity;
import android.opengl.GLSurfaceView;
import android.os.Bundle;
import android.util.FloatMath;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
public class MainActivity extends Activity implements OnTouchListener {
private GLSurfaceView mGLView;
float oldx = 0, oldy = 0;
private HelloOpenGLES10Renderer m;
ProgressDialogThread p;
ProgressDialogThread123 t;
boolean stop = true;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mGLView = new GLSurfaceView(this);
m = new HelloOpenGLES10Renderer();
mGLView.setRenderer(m);
mGLView.setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);
setContentView(mGLView);
mGLView.setOnTouchListener(this);
p = new ProgressDialogThread();
}
#Override
protected void onPause() {
super.onPause();
mGLView.onPause();
p.stop();
stop = false;
}
#Override
protected void onResume() {
super.onResume();
mGLView.onResume();
t = new ProgressDialogThread123();
t.start();
p.start();
}
/**
* gets u the random number btw 0.0 to 1.0
*/
public float getmearandom() {
Random rng = new Random();
float next = rng.nextFloat();
Integer i = rng.nextInt();
if (i % 2 == 0)
next = next * (-1);
return next;
}
class ProgressDialogThread123 extends Thread {
#Override
public void run() {
// TODO Auto-generated method stub
super.run();
for (; stop;) {
p.run();
}
}
}
class ProgressDialogThread extends Thread {
#Override
public void run() {
super.run();
if (stop) {
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
e.printStackTrace();
}
m.x = getmearandom();
m.y = getmearandom();
Log.i("m.x=" + m.x + ":", "m.y=" + m.y);
mGLView.requestRender();
}
}
}
#Override
public boolean onTouch(View v, MotionEvent event) {
float x = event.getX();
float y = event.getY();
float x1 = ((x * 2) / 480);
float y1 = ((y * 2) / 724);
x1 = -1 + x1;
y1 = -1 + y1;
if (y < 362) {
if (y1 > 0)
y1 = -y1;
} else if (y > 362) {
if (y1 < 0)
y1 = -y1;
} else {
y1 = 0;
}
if (x > 240) {
if (x1 < 0)
x1 = -x1;
} else if (x < 240) {
if (x1 > 0)
x1 = -x1;
} else {
x1 = 0;
}
Log.i("x1=" + x1, "y1=" + y1);
float d = (((m.x - x1) * (m.x - x1)) + ((m.y - y1) * (m.y - y1)));
float dd = FloatMath.sqrt(d);
if (dd <= 0.10f) {
m.color = true;
// mGLView.requestRender();
Log.i("Tag", "Circle");
}
// m.x += 0.10f;
return true;
}
}
Please anyone help me !! thanks in advance
If you are only drawing in 2d I suggest you loose "frustum" and "lookAt" and replace them with "ortho" with coordinates: ortho(viewOrigin.x, viewOrigin.x + viewSize.width, viewOrigin.y + viewSize.height, viewOrigin.y, -1.0f, 1.0f). This will make your GL coordinate system same as your view coordinates. As for circle vertices rather create them with radius of 1.0f. Now to draw the circle, before the draw call you just have to "push" matrix, translate to screen coordinates (X, Y, .0f), scale to radius R in pixels (R, R, 1.0f) and "pop" the matrix after the call.. Now to check on touch if the circle was hit:
`bool didHit = ((touch.x-cicrcleCenter.x)*(touch.x-cicrcleCenter.x) +
(touch.y-cicrcleCenter.y)*(touch.y-cicrcleCenter.y))
< R*R`;
Note that "viewOrigin" in "ortho" depends on where you are catching touches: If you are catching them in the same view it will probably be at (0,0) no matter where the view is. Those coordinates should correspond to coordinates you receive in your touch event when pressing at upper left and bottom right corners of your view.
If you really need to draw in 3d and you will have to use frustum, you will need to get inverse of your projection matrix to create 3d rays from your touches and then check for hits the same way you would for bullets if you like.
I've been trying to create my own sphere using OpenGL ES and I followed the math described here http://www.math.montana.edu/frankw/ccp/multiworld/multipleIVP/spherical/learn.htm
However when I draw the sphere (just the vertices), just half of the sphere is been drawn. Can you please point to me what is the exact problem in the code that I am giving below:
public class Sphere {
static private FloatBuffer sphereVertex;
static private FloatBuffer sphereNormal;
static float sphere_parms[]=new float[3];
double mRaduis;
double mStep;
float mVertices[];
private static double DEG = Math.PI/180;
int mPoints;
/**
* The value of step will define the size of each facet as well as the number of facets
*
* #param radius
* #param step
*/
public Sphere( float radius, double step) {
this.mRaduis = radius;
this.mStep = step;
sphereVertex = FloatBuffer.allocate(40000);
mPoints = build();
Log.d("ALIS CHECK!!!!!!", " COUNT:" + mPoints);
}
public void draw(GL10 gl) {
gl.glFrontFace(GL10.GL_CW);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, sphereVertex);
gl.glColor4f(1.0f, 0.0f, 0.0f, 1.0f);
gl.glDrawArrays(GL10.GL_POINTS, 0, mPoints);
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
}
private int build() {
/**
* x = p * sin(phi) * cos(theta)
* y = p * sin(phi) * sin(theta)
* z = p * cos(phi)
*/
double dTheta = mStep * DEG;
double dPhi = dTheta;
int points = 0;
for(double phi = -(Math.PI/2); phi <= Math.PI/2; phi+=dPhi) {
//for each stage calculating the slices
for(double theta = 0.0; theta <= (Math.PI * 2); theta+=dTheta) {
sphereVertex.put((float) (mRaduis * Math.sin(phi) * Math.cos(theta)) );
sphereVertex.put((float) (mRaduis * Math.sin(phi) * Math.sin(theta)) );
sphereVertex.put((float) (mRaduis * Math.cos(phi)) );
points++;
}
}
sphereVertex.position(0);
return points;
}
}
Also here is my renderer class:
/**
* These values are used to rotate the image by a certain value
*/
private float xRot;
private float yRot;
public void setxRot(float xRot) {
this.xRot += xRot;
}
public void setyRot(float yRot) {
this.yRot += yRot;
}
public GLViewRenderer(Context ctx) {
//initialize our 3D triangle here
mSphere = new Sphere(1, 25);
//Initializing the rate counter object
//This will help us in calculating the frames per second
fpsCalculator = new RateCounter(TAG);
fpsCalculator.start();
}
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
//initialize all the things required for openGL configurations
gl.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_NICEST);
}
public void onDrawFrame(GL10 gl) {
if(fpsCalculator != null)
fpsCalculator.countOnce();
//write the drawing code needed
gl.glClear(GL10.GL_COLOR_BUFFER_BIT);
gl.glLoadIdentity();
/**
* Change this value in z if you want to see the image zoomed in
*/
gl.glTranslatef(0.0f, 0.0f, -5.0f);
gl.glRotatef(xRot, 0.0f, 1.0f, 0.0f);
gl.glRotatef(yRot, 1.0f, 0.0f, 0.0f);
mSphere.draw(gl);
}
public void onSurfaceChanged(GL10 gl, int width, int height) {
if(height == 0) {
height = 1;
}
gl.glViewport(0, 0, width, height);
gl.glMatrixMode(GL10.GL_PROJECTION);
gl.glLoadIdentity();
//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
}
/**
* Used to stop the FPS counter
*/
public void pause() {
if(fpsCalculator != null)
fpsCalculator.stop();
}
}
I'd really appreciate some help on this.
P.S: I tried changing CW to CCW still no luck
Thanks
Change this
for(double phi = -(Math.PI/2); phi <= Math.PI/2; phi+=dPhi)
to this
for(double phi = -(Math.PI); phi <= Math.PI; phi+=dPhi)
Actually, changing
for(double phi = -(Math.PI/2); phi <= Math.PI/2; phi+=dPhi)
to
for(double phi = -(Math.PI); phi <= 0; phi+=dPhi)
is enough. With phi from -(Math.PI) to +(Math.PI) you are making 360 degrees turn and counting each point twice. You can also do:
for(double phi = -(Math.PI); phi <= Math.PI; phi+=dPhi) {
for(double theta = 0.0; theta <= (Math.PI); theta+=dTheta) {
...
}
}
to avoid counting twice.