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i create object 3d in android using tutorial from learnopengles, and i create cube from the lesson six of that tutorial (texture filtering), after that i want replace the cube with my object (i create the strawberry object). i want my object can display in the view, so i parsing the my object (my object use extension file .obj) to my renderer class, but the object in view is displaying random triangle object.
this is my parsing code :
public ObjLoader(Context mActivityContext) {
FileReader fr;
String str;
ArrayList<Float> tempModelVertices = new ArrayList<Float>();
ArrayList<Float> tempTextureVertices = new ArrayList<Float>();
ArrayList<Float> tempNormalVertices = new ArrayList<Float>();
ArrayList<Integer> facesM = new ArrayList<Integer>();
ArrayList<Integer> facesT = new ArrayList<Integer>();
ArrayList<Integer> facesN = new ArrayList<Integer>();
try {
fr = new FileReader(new File("model/straw_obj"));
BufferedReader br = new BufferedReader(fr);
while((str = br.readLine())!=null){
if(str.startsWith("f")){
String[] strAr = str.replaceAll("f", "").trim().split(" ");
for(String s : strAr){
String[] cornerAr = s.split("/");
facesM.add(Integer.parseInt(cornerAr[0].trim())-1);
facesT.add(Integer.parseInt(cornerAr[1].trim())-1);
facesN.add(Integer.parseInt(cornerAr[2].trim())-1);
}
}
else if(str.startsWith("vt")){
String[] strAr = str.replaceAll("vt", "").trim().split(" ");
tempTextureVertices.add(Float.valueOf(strAr[0].trim()));
tempTextureVertices.add(-1*Float.valueOf(strAr[1].trim()));
}
else if(str.startsWith("vn")){
String[] strAr = str.replaceAll("vn", "").trim().split(" ");
tempNormalVertices.add(Float.valueOf(strAr[0].trim()));
tempNormalVertices.add(Float.valueOf(strAr[1].trim()));
tempNormalVertices.add(Float.valueOf(strAr[2].trim()));
}
else if(str.startsWith("v")){
String[] strAr = str.replaceAll("v", "").trim().split(" ");
tempModelVertices.add(Float.valueOf(strAr[0].trim()));
tempModelVertices.add(Float.valueOf(strAr[1].trim()));
tempModelVertices.add(Float.valueOf(strAr[2].trim()));
}
}
//Log.v(LOG_TAG, "v :"+ String.valueOf(v) + "vt :"+ String.valueOf(vt) + "vn :"+ String.valueOf(vn) + "f :"+ String.valueOf(f));
} catch (IOException e) {
// TODO Auto-generated catch block
Log.v(TAG, "error");
}
Log.v(TAG, "vt " + String.valueOf(tempTextureVertices.size()) + " vn " + String.valueOf(tempNormalVertices.size()) + " v " + String.valueOf(tempModelVertices.size()));
ModelPositionData = new float[facesM.size()];
ModelTextureCoordinateData = new float[facesT.size()];
ModelNormalData = new float[facesN.size()];
for(int i=0; i<facesM.size(); i++){
ModelPositionData[i] = tempModelVertices.get(facesM.get(i));
}
for(int i=0; i<facesT.size(); i++){
ModelTextureCoordinateData[i] = tempTextureVertices.get(facesT.get(i));
}
for(int i=0; i<facesN.size(); i++){
ModelNormalData[i] = tempNormalVertices.get(facesN.get(i));
}
}
and this is how i create the glsurface renderer
public class TesterRenderer implements GLSurfaceView.Renderer{
private static final String TAG = "TesterRenderer";
private final Context mActivityContext;
/**
* Store the model matrix. This matrix is used to move models from object space (where each model can be thought
* of being located at the center of the universe) to world space.
*/
private float[] mModelMatrix = new float[16];
/**
* Store the view matrix. This can be thought of as our camera. This matrix transforms world space to eye space;
* it positions things relative to our eye.
*/
private float[] mViewMatrix = new float[16];
/** Store the projection matrix. This is used to project the scene onto a 2D viewport. */
private float[] mProjectionMatrix = new float[16];
/** Allocate storage for the final combined matrix. This will be passed into the shader program. */
private float[] mMVPMatrix = new float[16];
/** Store the accumulated rotation. */
private final float[] mAccumulatedRotation = new float[16];
/** Store the current rotation. */
private final float[] mCurrentRotation = new float[16];
/** A temporary matrix. */
private float[] mTemporaryMatrix = new float[16];
/**
* Stores a copy of the model matrix specifically for the light position.
*/
private float[] mLightModelMatrix = new float[16];
/** Store our model data in a float buffer. */
private final FloatBuffer mModelPositions;
private final FloatBuffer mModelNormals;
private final FloatBuffer mModelTextureCoordinates;
// private final FloatBuffer mModelTextureCoordinatesForPlane;
/** This will be used to pass in the transformation matrix. */
private int mMVPMatrixHandle;
/** This will be used to pass in the modelview matrix. */
private int mMVMatrixHandle;
/** This will be used to pass in the light position. */
private int mLightPosHandle;
/** This will be used to pass in the texture. */
private int mTextureUniformHandle;
/** This will be used to pass in model position information. */
private int mPositionHandle;
/** This will be used to pass in model normal information. */
private int mNormalHandle;
/** This will be used to pass in model texture coordinate information. */
private int mTextureCoordinateHandle;
/** How many bytes per float. */
private final int mBytesPerFloat = 4;
/** Size of the position data in elements. */
private final int mPositionDataSize = 3;
/** Size of the normal data in elements. */
private final int mNormalDataSize = 3;
/** Size of the texture coordinate data in elements. */
private final int mTextureCoordinateDataSize = 2;
/** Used to hold a light centered on the origin in model space. We need a 4th coordinate so we can get translations to work when
* we multiply this by our transformation matrices. */
private final float[] mLightPosInModelSpace = new float[] {0.0f, 0.0f, 0.0f, 1.0f};
/** Used to hold the current position of the light in world space (after transformation via model matrix). */
private final float[] mLightPosInWorldSpace = new float[4];
/** Used to hold the transformed position of the light in eye space (after transformation via modelview matrix) */
private final float[] mLightPosInEyeSpace = new float[4];
/** This is a handle to our cube shading program. */
private int mProgramHandle;
/** This is a handle to our light point program. */
private int mPointProgramHandle;
/** These are handles to our texture data. */
private int mTextureDataHandle;
// private int mGrassDataHandle;
/** Temporary place to save the min and mag filter, in case the activity was restarted. */
private int mQueuedMinFilter;
private int mQueuedMagFilter;
// These still work without volatile, but refreshes are not guaranteed to happen.
public volatile float mDeltaX;
public volatile float mDeltaY;
public TesterRenderer(final Context activityContext)
{
mActivityContext = activityContext;
ObjLoader obj = new ObjLoader(mActivityContext);
mModelPositions = ByteBuffer.allocateDirect(obj.ModelPositionData.length * mBytesPerFloat)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
mModelPositions.put(obj.ModelPositionData).position(0);
mModelNormals = ByteBuffer.allocateDirect(obj.ModelNormalData.length * mBytesPerFloat)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
mModelNormals.put(obj.ModelNormalData).position(0);
mModelTextureCoordinates = ByteBuffer.allocateDirect(obj.ModelTextureCoordinateData.length * mBytesPerFloat)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
mModelTextureCoordinates.put(obj.ModelTextureCoordinateData).position(0);
}
#Override
public void onSurfaceCreated(GL10 glUnused, EGLConfig config)
{
// Set the background clear color to black.
GLES20.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
// Use culling to remove back faces.
GLES20.glEnable(GLES20.GL_CULL_FACE);
// Enable depth testing
GLES20.glEnable(GLES20.GL_DEPTH_TEST);
// The below glEnable() call is a holdover from OpenGL ES 1, and is not needed in OpenGL ES 2.
// Enable texture mapping
// GLES20.glEnable(GLES20.GL_TEXTURE_2D);
// Position the eye in front of the origin.
final float eyeX = 0.0f;
final float eyeY = 0.0f;
final float eyeZ = -0.5f;
// We are looking toward the distance
final float lookX = 0.0f;
final float lookY = 0.0f;
final float lookZ = -5.0f;
// Set our up vector. This is where our head would be pointing were we holding the camera.
final float upX = 0.0f;
final float upY = 1.0f;
final float upZ = 0.0f;
// Set the view matrix. This matrix can be said to represent the camera position.
// NOTE: In OpenGL 1, a ModelView matrix is used, which is a combination of a model and
// view matrix. In OpenGL 2, we can keep track of these matrices separately if we choose.
Matrix.setLookAtM(mViewMatrix, 0, eyeX, eyeY, eyeZ, lookX, lookY, lookZ, upX, upY, upZ);
final String vertexShader = RawResourceReader.readTextFileFromRawResource(mActivityContext, R.raw.per_pixel_vertex_shader_tex_and_light);
final String fragmentShader = RawResourceReader.readTextFileFromRawResource(mActivityContext, R.raw.per_pixel_fragment_shader_tex_and_light);
final int vertexShaderHandle = ShaderHelper.compileShader(GLES20.GL_VERTEX_SHADER, vertexShader);
final int fragmentShaderHandle = ShaderHelper.compileShader(GLES20.GL_FRAGMENT_SHADER, fragmentShader);
mProgramHandle = ShaderHelper.createAndLinkProgram(vertexShaderHandle, fragmentShaderHandle,
new String[] {"a_Position", "a_Normal", "a_TexCoordinate"});
// Define a simple shader program for our point.
final String pointVertexShader = RawResourceReader.readTextFileFromRawResource(mActivityContext, R.raw.point_vertex_shader);
final String pointFragmentShader = RawResourceReader.readTextFileFromRawResource(mActivityContext, R.raw.point_fragment_shader);
final int pointVertexShaderHandle = ShaderHelper.compileShader(GLES20.GL_VERTEX_SHADER, pointVertexShader);
final int pointFragmentShaderHandle = ShaderHelper.compileShader(GLES20.GL_FRAGMENT_SHADER, pointFragmentShader);
mPointProgramHandle = ShaderHelper.createAndLinkProgram(pointVertexShaderHandle, pointFragmentShaderHandle,
new String[] {"a_Position"});
// Load the texture
mTextureDataHandle = TextureHelper.loadTexture(mActivityContext, R.drawable.strawberry_texture);
GLES20.glGenerateMipmap(GLES20.GL_TEXTURE_2D);
// mGrassDataHandle = TextureHelper.loadTexture(mActivityContext, R.drawable.noisy_grass_public_domain);
// GLES20.glGenerateMipmap(GLES20.GL_TEXTURE_2D);
if (mQueuedMinFilter != 0)
{
setMinFilter(mQueuedMinFilter);
}
if (mQueuedMagFilter != 0)
{
setMagFilter(mQueuedMagFilter);
}
// Initialize the accumulated rotation matrix
Matrix.setIdentityM(mAccumulatedRotation, 0);
}
#Override
public void onSurfaceChanged(GL10 glUnused, int width, int height)
{
// Set the OpenGL viewport to the same size as the surface.
GLES20.glViewport(0, 0, width, height);
// Create a new perspective projection matrix. The height will stay the same
// while the width will vary as per aspect ratio.
final float ratio = (float) width / height;
final float left = -ratio;
final float right = ratio;
final float bottom = -1.0f;
final float top = 1.0f;
final float near = 1.0f;
final float far = 1000.0f;
Matrix.frustumM(mProjectionMatrix, 0, left, right, bottom, top, near, far);
}
#Override
public void onDrawFrame(GL10 glUnused)
{
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT | GLES20.GL_DEPTH_BUFFER_BIT);
// Do a complete rotation every 10 seconds.
long time = SystemClock.uptimeMillis() % 10000L;
long slowTime = SystemClock.uptimeMillis() % 100000L;
float angleInDegrees = (360.0f / 10000.0f) * ((int) time);
float slowAngleInDegrees = (360.0f / 100000.0f) * ((int) slowTime);
// Set our per-vertex lighting program.
GLES20.glUseProgram(mProgramHandle);
// Set program handles for cube drawing.
mMVPMatrixHandle = GLES20.glGetUniformLocation(mProgramHandle, "u_MVPMatrix");
mMVMatrixHandle = GLES20.glGetUniformLocation(mProgramHandle, "u_MVMatrix");
mLightPosHandle = GLES20.glGetUniformLocation(mProgramHandle, "u_LightPos");
mTextureUniformHandle = GLES20.glGetUniformLocation(mProgramHandle, "u_Texture");
mPositionHandle = GLES20.glGetAttribLocation(mProgramHandle, "a_Position");
mNormalHandle = GLES20.glGetAttribLocation(mProgramHandle, "a_Normal");
mTextureCoordinateHandle = GLES20.glGetAttribLocation(mProgramHandle, "a_TexCoordinate");
// Calculate position of the light. Rotate and then push into the distance.
Matrix.setIdentityM(mLightModelMatrix, 0);
Matrix.translateM(mLightModelMatrix, 0, 0.0f, 0.0f, -2.0f);
Matrix.rotateM(mLightModelMatrix, 0, angleInDegrees, 0.0f, 1.0f, 0.0f);
Matrix.translateM(mLightModelMatrix, 0, 0.0f, 0.0f, 3.5f);
Matrix.multiplyMV(mLightPosInWorldSpace, 0, mLightModelMatrix, 0, mLightPosInModelSpace, 0);
Matrix.multiplyMV(mLightPosInEyeSpace, 0, mViewMatrix, 0, mLightPosInWorldSpace, 0);
// Draw a cube.
// Translate the cube into the screen.
Matrix.setIdentityM(mModelMatrix, 0);
Matrix.translateM(mModelMatrix, 0, 0.0f, 0.0f, -7.0f);
// Set a matrix that contains the current rotation.
Matrix.setIdentityM(mCurrentRotation, 0);
Matrix.rotateM(mCurrentRotation, 0, mDeltaX, 0.0f, 1.0f, 0.0f);
Matrix.rotateM(mCurrentRotation, 0, mDeltaY, 1.0f, 0.0f, 0.0f);
mDeltaX = 0.0f;
mDeltaY = 0.0f;
// Multiply the current rotation by the accumulated rotation, and then set the accumulated rotation to the result.
Matrix.multiplyMM(mTemporaryMatrix, 0, mCurrentRotation, 0, mAccumulatedRotation, 0);
System.arraycopy(mTemporaryMatrix, 0, mAccumulatedRotation, 0, 16);
// Rotate the cube taking the overall rotation into account.
Matrix.multiplyMM(mTemporaryMatrix, 0, mModelMatrix, 0, mAccumulatedRotation, 0);
System.arraycopy(mTemporaryMatrix, 0, mModelMatrix, 0, 16);
// Set the active texture unit to texture unit 0.
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
// Bind the texture to this unit.
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mTextureDataHandle);
// Tell the texture uniform sampler to use this texture in the shader by binding to texture unit 0.
GLES20.glUniform1i(mTextureUniformHandle, 0);
// Pass in the texture coordinate information
GLES20.glEnableVertexAttribArray(mTextureCoordinateHandle);
mModelTextureCoordinates.position(0);
GLES20.glVertexAttribPointer(mTextureCoordinateHandle, mTextureCoordinateDataSize, GLES20.GL_FLOAT, false,
0, mModelTextureCoordinates);
drawModel();
// Draw a plane
Matrix.setIdentityM(mModelMatrix, 0);
Matrix.translateM(mModelMatrix, 0, 0.0f, -2.0f, -5.0f);
Matrix.scaleM(mModelMatrix, 0, 25.0f, 1.0f, 25.0f);
Matrix.rotateM(mModelMatrix, 0, slowAngleInDegrees, 0.0f, 1.0f, 0.0f);
// Set the active texture unit to texture unit 0.
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
// Bind the texture to this unit.
//GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mGrassDataHandle);
// Tell the texture uniform sampler to use this texture in the shader by binding to texture unit 0.
GLES20.glUniform1i(mTextureUniformHandle, 0);
// Pass in the texture coordinate information
GLES20.glEnableVertexAttribArray(mTextureCoordinateHandle);
drawModel();
GLES20.glUseProgram(mPointProgramHandle);
drawLight();
}
public void setMinFilter(final int filter)
{
if (mTextureDataHandle != 0)
{
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mTextureDataHandle);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, filter);
// GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mGrassDataHandle);
// GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, filter);
}
else
{
mQueuedMinFilter = filter;
}
}
public void setMagFilter(final int filter)
{
if (mTextureDataHandle != 0)
{
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mTextureDataHandle);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, filter);
// GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mGrassDataHandle);
// GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, filter);
}
else
{
mQueuedMagFilter = filter;
}
}
private void drawModel()
{
// Pass in the position information
GLES20.glEnableVertexAttribArray(mPositionHandle);
mModelPositions.position(0);
GLES20.glVertexAttribPointer(mPositionHandle, mPositionDataSize, GLES20.GL_FLOAT, false,
0, mModelPositions);
// Pass in the normal information
GLES20.glEnableVertexAttribArray(mNormalHandle);
mModelNormals.position(0);
GLES20.glVertexAttribPointer(mNormalHandle, mNormalDataSize, GLES20.GL_FLOAT, false,
0, mModelNormals);
// This multiplies the view matrix by the model matrix, and stores the result in the MVP matrix
// (which currently contains model * view).
Matrix.multiplyMM(mMVPMatrix, 0, mViewMatrix, 0, mModelMatrix, 0);
// Pass in the modelview matrix.
GLES20.glUniformMatrix4fv(mMVMatrixHandle, 1, false, mMVPMatrix, 0);
// This multiplies the modelview matrix by the projection matrix, and stores the result in the MVP matrix
// (which now contains model * view * projection).
Matrix.multiplyMM(mTemporaryMatrix, 0, mProjectionMatrix, 0, mMVPMatrix, 0);
System.arraycopy(mTemporaryMatrix, 0, mMVPMatrix, 0, 16);
// Pass in the combined matrix.
GLES20.glUniformMatrix4fv(mMVPMatrixHandle, 1, false, mMVPMatrix, 0);
// Pass in the light position in eye space.
GLES20.glUniform3f(mLightPosHandle, mLightPosInEyeSpace[0], mLightPosInEyeSpace[1], mLightPosInEyeSpace[2]);
// Draw the cube.
GLES20.glDrawArrays(GLES20.GL_TRIANGLES, 0, 36);
}
/**
* Draws a point representing the position of the light.
*/
private void drawLight()
{
final int pointMVPMatrixHandle = GLES20.glGetUniformLocation(mPointProgramHandle, "u_MVPMatrix");
final int pointPositionHandle = GLES20.glGetAttribLocation(mPointProgramHandle, "a_Position");
// Pass in the position.
GLES20.glVertexAttrib3f(pointPositionHandle, mLightPosInModelSpace[0], mLightPosInModelSpace[1], mLightPosInModelSpace[2]);
// Since we are not using a buffer object, disable vertex arrays for this attribute.
GLES20.glDisableVertexAttribArray(pointPositionHandle);
// Pass in the transformation matrix.
Matrix.multiplyMM(mMVPMatrix, 0, mViewMatrix, 0, mLightModelMatrix, 0);
Matrix.multiplyMM(mTemporaryMatrix, 0, mProjectionMatrix, 0, mMVPMatrix, 0);
System.arraycopy(mTemporaryMatrix, 0, mMVPMatrix, 0, 16);
GLES20.glUniformMatrix4fv(pointMVPMatrixHandle, 1, false, mMVPMatrix, 0);
// Draw the point.
GLES20.glDrawArrays(GLES20.GL_POINTS, 0, 1);
}
}
can someone help me fix this ?
It looks like there is a problem with the way you reorder the coordinates based on the indices in the faces:
for(int i=0; i<facesM.size(); i++){
ModelPositionData[i] = tempModelVertices.get(facesM.get(i));
}
Each position consists of 3 coordinates. This loop copies only one value per position, though. It should look something like this:
for(int i=0; i<facesM.size(); i++){
ModelPositionData[3 * i ] = tempModelVertices.get(3 * facesM.get(i) );
ModelPositionData[3 * i + 1] = tempModelVertices.get(3 * facesM.get(i) + 1);
ModelPositionData[3 * i + 2] = tempModelVertices.get(3 * facesM.get(i) + 2);
}
You will also need to adjust the allocation accordingly:
ModelPositionData = new float[3 * facesM.size()];
and make the equivalent changes for the normals and texture coordinates.
I want to rotate the object z axis so I am using the below code but its not rotating at particular position its rotation just go back and appear come near. I think there is wrong with the values in GLU.gluLookAt(gl, 0, 0, 10, 0, 0, 0, 0, 1, 0);. Please help me to set the correct values of these So that rotation works well.
gl.glTranslatef(mOrigin.x, mOrigin.y, mOrigin.z);
gl.glRotatef(mRotate.x, 1f, 0f, 0f);
gl.glRotatef(mRotate.y, 0f, 1f, 0f);
gl.glRotatef(mRotate.z, 0f, 0f, 1f);
private class Renderer implements GLSurfaceView.Renderer {
public Renderer() {
setEGLConfigChooser(8, 8, 8, 8, 16, 0);
getHolder().setFormat(PixelFormat.TRANSLUCENT);
setZOrderOnTop(true);
}
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
gl.glClearColor(0.0f,0.0f,0.0f, 0.0f);
gl.glEnable(GL10.GL_DEPTH_TEST);
gl.glDepthFunc(GL10.GL_LEQUAL);
gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_NICEST);
gl.glEnable(GL10.GL_TEXTURE_2D);
gl.glShadeModel(GL10.GL_SMOOTH);
}
public void onSurfaceChanged(GL10 gl, int w, int h) {
mViewWidth = (float)w;
mViewHeight = (float)h;
gl.glViewport(0,0,w,h);
gl.glMatrixMode(GL10.GL_PROJECTION);
gl.glLoadIdentity();
GLU.gluPerspective(gl, 45, mViewWidth/mViewHeight, 0.1f, 100f);
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
}
public void onDrawFrame(GL10 gl) {
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
gl.glPushMatrix();
gl.glDisable(GL10.GL_DITHER);
GLU.gluLookAt(gl, 0, 0, 10, 0, 0, 0, 0, 1, 0);
//draw_model
gl.glPushMatrix();
if(mOrigin != null && mRotate != null) {
gl.glTranslatef(mOrigin.x, mOrigin.y, mOrigin.z);
gl.glRotatef(mRotate.x, 1f, 0f, 0f);
gl.glRotatef(mRotate.y, 0f, 1f, 0f);
gl.glRotatef(mRotate.z, 0f, 0f, 1f);
}
if(mModel != null) {
mModel.draw(gl, mContext);
if(!RendererView.textureFileName.equals(""))
mModel.bindTextures(mContext, gl);
}
gl.glPopMatrix();
gl.glPopMatrix();
if(isPictureTake) {
w = getWidth();
h = getHeight();
b = new int[w*(y+h)];
bt = new int[w*h];
IntBuffer ib = IntBuffer.wrap(b);
ib.position(0);
gl.glReadPixels(0, 0, w, h, GL10.GL_RGBA, GL10.GL_UNSIGNED_BYTE, ib);
createBitmapFromGLSurface(mContext);
isPictureTake = false;
}
}
}
ObjLoader.java
package com.amplimesh.models;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import java.util.ArrayList;
import java.util.StringTokenizer;
import javax.microedition.khronos.opengles.GL10;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.opengl.GLUtils;
import com.amplimesh.renderer.RendererView;
import com.amplimesh.util.Point3;
/**
* Object Loader and draw the texture and object.
* #author Ajay
*/
public class ObjModel {
/**
* It fill the texture into the mesh
* #param context
* #param gl
*/
public void bindTextures(Context context, GL10 gl) {
Bitmap bitmap;
try {
InputStream is = context.getAssets().open("textures/"+RendererView.textureFileName);
bitmap = BitmapFactory.decodeStream(is);
if(bitmap != null) {
// generate one texture pointer
gl.glGenTextures(1, mTextures, 0);
// ...and bind it to our array
gl.glBindTexture(GL10.GL_TEXTURE_2D, mTextures[0]);
// create nearest filtered texture
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_LINEAR);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MAG_FILTER, GL10.GL_LINEAR);
//Different possible texture parameters, e.g. GL10.GL_CLAMP_TO_EDGE
//gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_S, GL10.GL_REPEAT);
//gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_T, GL10.GL_REPEAT);
// 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();
}
} catch (java.io.IOException e) {
return;
}
}
/**
* It draw the object.
* #param gl
*/
public void draw(GL10 gl, Context mContext) {
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
gl.glEnableClientState(GL10.GL_NORMAL_ARRAY);
for (Model model : mModels) {
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, model.v);
if (model.vt != null && mTextures != null) {
gl.glBindTexture(GL10.GL_TEXTURE_2D, mTextures[0]);
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, model.vt);
}
if (model.vn != null) {
gl.glNormalPointer(GL10.GL_FLOAT, 0, model.vn);
}
gl.glDrawArrays(GL10.GL_TRIANGLES, 0, model.v_size);
}
gl.glDisableClientState(GL10.GL_NORMAL_ARRAY);
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
}
/**
* It Load the object from stream.
* #param is
* #param texture_name
* #return
* #throws IOException
*/
public static ObjModel loadFromStream(InputStream is, String texture_name) throws IOException {
ObjModel obj = ObjLoader.loadFromStream(is);
return obj;
}
private Model mModels[];
private int mTextures[] = new int[1];;
/**
* It read the the obj file.
* #author Ajay
*/
private static class ObjLoader {
public static ObjModel loadFromStream(InputStream is) throws IOException {
BufferedReader reader = new BufferedReader(new InputStreamReader(is));
ObjModel obj = new ObjModel();
ArrayList<Point3> v = new ArrayList<Point3>();
ArrayList<Point3> vt = new ArrayList<Point3>();
ArrayList<Point3> vn = new ArrayList<Point3>();
ArrayList<Face> f = new ArrayList<Face>();
ArrayList<Model> o = new ArrayList<Model>();
boolean o_pending=false;
while(reader.ready()) {
String line = reader.readLine();
if (line == null)
break;
StringTokenizer tok = new StringTokenizer(line);
String cmd = tok.nextToken();
if (cmd.equals("o")) {
if (o_pending) {
Model model = new Model();
model.fill(f, vt.size() > 0, vn.size() > 0);
o.add(model);
}
else {
o_pending=true;
}
}
else
if (cmd.equals("v")) {
v.add(read_point(tok));
}
else
if (cmd.equals("vn")) {
vn.add(read_point(tok));
}
else
if (cmd.equals("vt")) {
vt.add(read_point(tok));
}
else
if (cmd.equals("f")) {
if (tok.countTokens() != 3)
continue;
Face face = new Face(3);
while (tok.hasMoreTokens()) {
StringTokenizer face_tok = new StringTokenizer(tok.nextToken(), "/");
int v_idx = -1;
int vt_idx = -1;
int vn_idx = -1;
v_idx = Integer.parseInt(face_tok.nextToken());
if (face_tok.hasMoreTokens()) vt_idx = Integer.parseInt(face_tok.nextToken());
if (face_tok.hasMoreTokens()) vn_idx = Integer.parseInt(face_tok.nextToken());
//Log.v("objmodel", "face: "+v_idx+"/"+vt_idx+"/"+vn_idx);
face.addVertex(
v.get(v_idx-1),
vt_idx == -1 ? null : vt.get(vt_idx-1),
vn_idx == -1 ? null : vn.get(vn_idx-1)
);
}
f.add(face);
}
}
if (o_pending) {
Model model = new Model();
model.fill(f, vt.size() > 0, vn.size() > 0);
o.add(model);
}
obj.mModels = new Model[o.size()];
o.toArray(obj.mModels);
return obj;
}
private static Point3 read_point(StringTokenizer tok) {
Point3 ret = new Point3();
if (tok.hasMoreTokens()) {
ret.x = Float.parseFloat(tok.nextToken());
if (tok.hasMoreTokens()) {
ret.y = Float.parseFloat(tok.nextToken());
if (tok.hasMoreTokens()) {
ret.z = Float.parseFloat(tok.nextToken());
}
}
}
return ret;
}
}
private static class Face {
Point3 v[];
Point3 vt[];
Point3 vn[];
int size;
int count;
public Face(int size) {
this.size = size;
this.count = 0;
this.v = new Point3[size];
this.vt = new Point3[size];
this.vn = new Point3[size];
}
public boolean addVertex(Point3 v, Point3 vt, Point3 vn) {
if (count >= size)
return false;
this.v[count] = v;
this.vt[count] = vt;
this.vn[count] = vn;
count++;
return true;
}
public void pushOnto(FloatBuffer v_buffer, FloatBuffer vt_buffer, FloatBuffer vn_buffer) {
int i;
for (i=0; i<size; i++) {
v_buffer.put(v[i].x); v_buffer.put(v[i].y); v_buffer.put(v[i].z);
if (vt_buffer != null && vt[i] != null) {
vt_buffer.put(vt[i].x); vt_buffer.put(vt[i].y);
}
if (vn_buffer != null && vn[i] != null) {
vn_buffer.put(vn[i].x); vn_buffer.put(vn[i].y); vn_buffer.put(vn[i].z);
}
}
}
}
/**
* It hold the vertex buffer, vertex normal and texture.
* #author Ajay
*/
private static class Model {
public FloatBuffer v;
public FloatBuffer vt;
public FloatBuffer vn;
public int v_size;
public void fill(ArrayList<Face> faces, boolean has_tex, boolean has_normals) {
int f_len = faces.size();
this.v_size = f_len * 3;
ByteBuffer tBuf = ByteBuffer.allocateDirect(this.v_size*3 * 4);
tBuf.order(ByteOrder.nativeOrder());
this.v = tBuf.asFloatBuffer();
if (has_tex) {
ByteBuffer vtBuf = ByteBuffer.allocateDirect(this.v_size*3 * 4);
vtBuf.order(ByteOrder.nativeOrder());
this.vt = vtBuf.asFloatBuffer();
}
if (has_normals) {
ByteBuffer vnBuf = ByteBuffer.allocateDirect(this.v_size*3 * 4);
vnBuf.order(ByteOrder.nativeOrder());
this.vn = vnBuf.asFloatBuffer();
}
int i;
for (i=0; i < f_len; i++) {
Face face = faces.get(i);
face.pushOnto(this.v, this.vt, this.vn);
}
this.v.rewind();
if (this.vt != null)
this.vt.rewind();
if (this.vn != null)
this.vn.rewind();
}
}
}
To rotate an object at a specific position around an axis, you first need to translate the object's center to the origin. In your example, you have an object at (mOrigin) which may be relative to another translation (your camera's position).
Instead of translating your object to its final position and then rotating, you need to translate it to (0,0,0), rotate and then translate to the final position.
In the simplest case this would be:
gl.glRotatef (mRotate.x, 1f, 0f, 0f);
gl.glRotatef (mRotate.y, 0f, 1f, 0f);
gl.glRotatef (mRotate.z, 0f, 0f, 1f);
gl.glTranslatef (mOrigin.x, mOrigin.y, mOrigin.z);
In the more complicated case, where your object is relative to the camera, you would have to do something like this:
gl.glTranslatef (-Camera.x, -Camera.y, -Camera.z);
gl.glRotatef (mRotate.x, 1f, 0f, 0f);
gl.glRotatef (mRotate.y, 0f, 1f, 0f);
gl.glRotatef (mRotate.z, 0f, 0f, 1f);
gl.glTranslatef (Camera.x + mOrigin.x, Camera.y + mOrigin.y, Camera.z + mOrigin.z);
The rotation component of the Glulookat seems fine so I dont see any problem there that may cause issues.
First, from the link you provided, it seems to me that you want to rotate about the Y axis although you mentioned the rotation about the Z axis this can give different results. https://www.dropbox.com/s/ozt7beo4gz5q293/demo2__A.avi
Second, what are the values you are using within the m_Rotate vector? are they in degrees or radians?
third, are you pushing or popping the matrix stack? if so how? or are you feeding your own matrix data into the OpenGL?
also have you made sure to call glLoadIdentity() to set the view matrix back to identity matrix during your draw calls?
TBH there can be many areas that may cause issue. To narrow down the possible problem area, do the followings in your draw function;
stop using GluLookAt.
remove all push and pop calls,
firstly make sure to call
glLoadIdentity();
translate your camera behind the object (in your GLuLookAt this is set to 0,0,10).
glTranslatef(0.0f,0.0f,-10.0f);
then do simple rotation around the Z axis by;
glRotatef(mRotate.z, 0.0f, 0.0f, 1.0f);
EDIT: you call onDrawFrame to draw things on the scene as far as I can tell. . and in this call where you need to do these changes to figure out where your problem is.
instead of this;
public void onDrawFrame(GL10 gl) {
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
gl.glPushMatrix();
gl.glDisable(GL10.GL_DITHER);
GLU.gluLookAt(gl, 0, 0, 10, 0, 0, 0, 0, 1, 0);
//draw_model
gl.glPushMatrix();
if(mOrigin != null && mRotate != null) {
gl.glTranslatef(mOrigin.x, mOrigin.y, mOrigin.z);
gl.glRotatef(mRotate.x, 1f, 0f, 0f);
gl.glRotatef(mRotate.y, 0f, 1f, 0f);
gl.glRotatef(mRotate.z, 0f, 0f, 1f);
}
...
gl.glPopMatrix();
gl.glPopMatrix();
}
try something simpler like this.
public void onDrawFrame(GL10 gl) {
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
gl.glDisable(GL10.GL_DITHER);
gl.glMatrixMode(GL10.GL_MODELVIEW); //making sure OpenGL currently in model view
gl.glLoadIdentity(); //clear the model view matrix to identity matrix
gl.glTranslatef(0.0f, 0.0f, -10.0f); //move 10 unit backwards so as if camera moves backwards.
gl.glRotatef(90.0f,0.0f,0.0f,1.0f) //rotate 90 degree around the z axis.
//draw_model
...
//gl.glPopMatrix();
//gl.glPopMatrix();
}
by doing so your possible problematic area reduced alot. and you can start figuring out the problem. if the above code works, then possible errors reduced alot.
it could be that;
you setting the matrix mode other then model view somewhere else and not setting it back in your draw call,
you are not clearing the identity matrix in your draw call.
your origin and rotation values are not correctly done.
BTW: Im not an expert in java but in c++ and objective c, we can not do 1f to set a value to float. we must use 1.0f otherwise compiler will complain.
Hy,
I want set only matrix in this code but if i use this statemant , it reset all drawing picture.
Bitmap a= Bitmap.createBitmap(src, 0, 0, src.getWidth(), src.getHeight(), matrix, true);
a need only new matrix but how i get it
I want only:
public static Bitmap flip(Bitmap src, int type) {
// create new matrix for transformation
Matrix matrix = new Matrix();
// if vertical
if(type == FLIP_VERTICAL) {
// y = y * -1
matrix.preScale(1.0f, -1.0f);
}
// if horizonal
else if(type == FLIP_HORIZONTAL) {
// x = x * -1
matrix.preScale(-1.0f, 1.0f);
// unknown type
} else {
return null;
}
// return transformed image
//Bitmap.createBitmap(src, 0, 0, src.getWidth(), src.getHeight(), matrix, true);
Bitmap pp= Bitmap.createBitmap(src, 0, 0, src.getWidth(), src.getHeight(), matrix, true);
return pp;
}
If oyu saw this Bitmao pp= ...
I want only change src ->matrix and that is all
I want to overlay an icon on top of 3D models in my game. I'm using gluProject to get the screen coordinates of the centre point of the models, and then using that data to draw icons on a custom view:
In my renderer class:
private void projectScreenCoords(GLSurfaceView view, GraphicsEntity ge, GL10 gl){
MatrixGrabber matrixGrabber = new MatrixGrabber();
matrixGrabber.getCurrentModelView(gl);
float[] modelMat = matrixGrabber.mModelView;
matrixGrabber.getCurrentProjection(gl);
float[] projMat = matrixGrabber.mProjection;
gl.glMatrixMode(GL10.GL_MODELVIEW);
// view port
int[] viewport = new int[]{view.getTop(),view.getLeft(),view.getWidth(),view.getHeight()};
float[] vector = new float[4];
GLU.gluProject(ge.getTransform().tx, ge.getTransform().ty, ge.getTransform().tz, modelMat, 0, projMat, 0, viewport, 0, vector, 0);
ge.setScreenCoords(vector[0], viewport[3] - vector[1]);
}
and my custom view:
protected void onDraw (Canvas canvas){
Vector<GraphicsEntity> scene = renderer.getForegroundScene();
for(int i = 0;i<scene.size();i++){
GraphicsEntity ge = scene.get(i);
float[] xy = ge.getScreenCoords();
if(xy[0]>-1 && xy[1]>-1){
canvas.drawBitmap(bitmap, xy[0]-bitmapWidth/2, xy[1]-bitmapHeight/2, null);
}
invalidate();
}
}
and where I set my projection matrix:
protected void setProjectionMatrix(GL10 gl){
float ratio = (float) viewportWidth / viewportHeight;
gl.glMatrixMode(GL10.GL_PROJECTION);
gl.glLoadIdentity();
gl.glFrustumf(-ratio*zoom, ratio*zoom, -1*zoom, 1*zoom, nearPlane, farPlane);
}
However, the further from the centre of the screen, the further off the centre of the model the icon is drawn:
Clearly, if it was just the viewport size that was incorrect (due to the bars at the top/bottom) then the icons would be off just in the y-axis, but they are off in the x-axis as well. What am I missing / doing wrong? Also I haven't used the 3rd value returned by gluProject, but this always has a value of 0.7 so I'm not quite sure how it would be used if at all?
Using SDK version 7, I've tested this on multiple devices (ZTE Blade running android 2.1 and Kindle Fire running 2.3.4) with the same results. viewportWidth/Height and view.getWidth/Height() are the same, and view.getTop/Left() returns 0. The MatrixGrabber code works for gluUnProject, so I'm reasonably confident that isn't the problem
EDIT: here is the rest of my GL-related drawing code:
In renderer:
// camera variables
protected float FOV = 60.0f;
protected float nearPlane = 3;
protected float farPlane = 7;
protected float eyeX = 0;
protected float eyeY = 0;
protected float eyeZ = 0;
protected float centreX = 0;
protected float centreY = 0;
protected float centreZ = ((farPlane - nearPlane) / 2) + nearPlane;
protected float upX = 0;
protected float upY = 1;
protected float upZ = 0;
protected float viewportWidth;
protected float viewportHeight;
// user camera control variables
protected float zoom = 1;
protected float rotatedX = 0;
protected float rotatedY = 0;
protected boolean zoomed = true;
protected TrackingTransform tracking;
protected void setWorldTransform(GL10 gl){
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
// transforms the centre position to 0,0,0
gl.glTranslatef(-centreX, -centreY, -centreZ);
}
protected void setModelRotation(GL10 gl, GraphicsEntity ge){
if(ge.isTrackerball()){
gl.glRotatef(rotatedX, 1.0f, 0, 0);
gl.glRotatef(rotatedY, 0, -1.0f, 0);
if(tracking!=null){
synchronized(tracking){
tracking.transform(gl);
}
}
} else if(ge.isBackground()){
gl.glTranslatef(centreX, centreY, centreZ);
gl.glRotatef(rotatedX, 1.0f, 0, 0);
gl.glRotatef(rotatedY, 0, -1.0f, 0);
if(ge.isSkybox()==true){
ge.getTransform().sx = nearPlane + 1.0f;
ge.getTransform().sy = nearPlane + 1.0f;
ge.getTransform().sz = nearPlane + 1.0f;
ge.getTransform().tx = 0;
ge.getTransform().ty = 0;
ge.getTransform().tz = 0;
}
}
}
protected void setModelViewMatrix(GL10 gl){
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
// not used:
//GLU.gluLookAt(gl, eyeX, eyeY, eyeZ, centreX, centreY, centreZ, upX, upY, upZ);
}
#Override
public void onDrawFrame(GL10 gl) {
// Set up various things before drawing
gl.glFrontFace(GL10.GL_CW);
gl.glEnable(GL10.GL_CULL_FACE);
gl.glCullFace(GL10.GL_FRONT);
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
gl.glEnable(GL10.GL_DEPTH_TEST);
// change projection matrix
float oldzoom = zoom;
zoom = 1.0f;
setProjectionMatrix(gl);
zoom = oldzoom;
// set global world transform (also changes to modelview)
setWorldTransform(gl);
// loop through and draw background models
for(int i = 0;i<backgroundGraphicsEntities.size();i++){
GraphicsEntity ge = backgroundGraphicsEntities.get(i);
SimpleTransform t = ge.getTransform();
int modelIndex = ge.getModelIndex();
if(modelIndex>=0){
gl.glPushMatrix();
setModelRotation(gl, ge);
t.transform(gl);
if(ge.isSprite() && gl11flag){
Sprite s = sprites.get(modelIndex);
s.draw((GL11) gl, ge);
} else {
Model m = models.get(modelIndex);
if(m!=null){
m.draw(gl);
}
}
gl.glPopMatrix();
}
if(i==0 && ge.isSkybox()){
// if skybox, reset depth bit
gl.glClear(GL10.GL_DEPTH_BUFFER_BIT);
}
}
gl.glClear(GL10.GL_DEPTH_BUFFER_BIT);
// change projection matrix (if zoomed)
setProjectionMatrix(gl);
// change back to modelview
gl.glMatrixMode(GL10.GL_MODELVIEW);
// loop through and draw models
for(int i = 0;i<graphicsEntities.size();i++){
GraphicsEntity ge = graphicsEntities.get(i);
SimpleTransform t = ge.getTransform();
int modelIndex = ge.getModelIndex();
if(modelIndex>=0){
gl.glPushMatrix();
setModelRotation(gl, ge);
t.transform(gl);
if(ge.isSprite() && gl11flag){
Sprite s = sprites.get(modelIndex);
s.draw((GL11) gl, ge);
} else {
Model m = models.get(modelIndex);
if(m!=null){
m.draw(gl);
}
if(projectScreenCoords){
projectScreenCoords(glSurfaceView, ge, gl);
}
}
gl.glPopMatrix();
}
}
#Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
viewportWidth = width;
viewportHeight = height;
gl.glViewport(0, 0, width, height);
setProjectionMatrix(gl);
}
#Override
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
if(gl instanceof GL11){
gl11flag = true;
}
gl.glClearColor(0, 0, 0, 1);
gl.glShadeModel(GL10.GL_SMOOTH);
gl.glEnable(GL10.GL_DEPTH_TEST);
gl.glDepthMask(true);
//gl.glClearDepthf(1.0f);
gl.glDepthFunc(GL10.GL_LEQUAL);
//gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_FASTEST);
setProjectionMatrix(gl);
}
and then in SimpleTransform (i.e. what gets called when ge.getTransform().transform(gl) is called):
public void transform(GL10 gl) {
gl.glTranslatef(tx, ty, tz);
gl.glRotatef(rz, 0, 0, 1);
gl.glRotatef(ry, 0, 1, 0);
gl.glRotatef(rx, 1, 0, 0);
gl.glScalef(sx, sy, sz);
}
and for TrackingTransform:
#Override
public void transform(GL10 gl) {
gl.glTranslatef(-tx, -ty, -tz);
}
and finally in model.draw():
public void draw(GL10 gl){
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
// Pass the vertex buffer in
gl.glVertexPointer(3, GL10.GL_FLOAT, 0,
vertices);
int textureID = material.getTexture().getTextureID();
if(textureID>=0){
// Enable Textures
gl.glEnable(GL10.GL_TEXTURE_2D);
// Get specific texture.
gl.glBindTexture(GL10.GL_TEXTURE_2D, textureID);
// Use UV coordinates.
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
// Pass in texture coordinates
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, textureCoordinates);
}
// Pass in vertex normals
gl.glNormalPointer(GL10.GL_FLOAT, 0, normals);
gl.glEnableClientState(GL10.GL_NORMAL_ARRAY);
gl.glDrawElements(GL10.GL_TRIANGLES, numindices,GL10.GL_UNSIGNED_SHORT, indices);
gl.glDisableClientState(GL10.GL_NORMAL_ARRAY);
if(textureID>=0){
// Disable buffers
gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
}
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
}
The problem wasn't in the gluProject code at all. In fact, it was to do with the translations done before calling gluProject:
In onDrawFrame:
Model m = models.get(modelIndex);
if(m!=null){
m.draw(gl);
gl.glTranslatef(-tracking.getTransform().tx, -tracking.getTransform().ty, -tracking.getTransform().tz);
if(tickcount % projectFrequency == 0 ){
projectScreenCoords(glSurfaceView, ge, gl);
}
}
I want rotate image in both the ways Clockwise as well as Anti clock wise.
I had try but not rotate image both the way,
so plz give me solution for my problem if you know..
Thanks in Advance.................///
Use the code below
public class Rotateimage extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_gallery);
// or just load a resource from the res/drawable directory:
Bitmap myBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.flo);
// find the width and height of the screen:
Display d = getWindowManager().getDefaultDisplay();
int x = d.getWidth();
int y = d.getHeight();
// get a reference to the ImageView component that will display the image:
ImageView img1 = (ImageView)findViewById(R.id.imageView1);
// scale it to fit the screen, x and y swapped because my image is wider than it is tall
Bitmap scaledBitmap = Bitmap.createScaledBitmap(myBitmap, y, x, true);
// create a matrix object
Matrix matrix = new Matrix();
matrix.postRotate(45, 90, 180);
// create a new bitmap from the original using the matrix to transform the result
Bitmap rotatedBitmap = Bitmap.createBitmap(scaledBitmap , 0, 0, scaledBitmap .getWidth(), scaledBitmap .getHeight(), matrix, true);
// display the rotated bitmap
img1.setImageBitmap(rotatedBitmap);
}}
Here is the base code to load a bitmap and rotate it left or right:
// Load a bitmap from a drawable, make sure this drawable exists in your project
Bitmap sprite = BitmapFactory.decodeResource(this.getResources(),
R.drawable.ic_launcher);
// Create two matrices that will be used to rotate the bitmap
Matrix rotateRight = new Matrix();
Matrix rotateLeft = new Matrix();
// Set the matrices with the desired rotation 90 or -90 degrees
rotateRight.preRotate(90);
rotateLeft.preRotate(-90);
// Create bitmaps based on the loaded bitmap 'sprite' and apply one of
// the rotation matrices
Bitmap rSprite = Bitmap.createBitmap(sprite, 0, 0,
sprite.getWidth(), sprite.getHeight(), rotateRight, true);
Bitmap lSprite = Bitmap.createBitmap(sprite, 0, 0,
sprite.getWidth(), sprite.getHeight(), rotateLeft, true);
Now go and use rSprite and lSprite.
Here is a full sample that actually draws the bitmaps to screen:
public class MainActivity extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(new drawView(this));
}
private class drawView extends View{
public drawView(Context context){
super(context);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
// Load a bitmap from a drawable, make sure this drawable exists in your project
Bitmap sprite = BitmapFactory.decodeResource(this.getResources(),
R.drawable.ic_launcher);
// Create two matrices that will be used to rotate the bitmap
Matrix rotateRight = new Matrix();
Matrix rotateLeft = new Matrix();
// Set the matrices with the desired rotation 90 or -90 degrees
rotateRight.preRotate(90);
rotateLeft.preRotate(-90);
// Create bitmaps based on the loaded bitmap 'sprite' and apply one of
// the rotation matrices
Bitmap rSprite = Bitmap.createBitmap(sprite, 0, 0,
sprite.getWidth(), sprite.getHeight(), rotateRight, true);
Bitmap lSprite = Bitmap.createBitmap(sprite, 0, 0,
sprite.getWidth(), sprite.getHeight(), rotateLeft, true);
//Draw the first unrotated sprite at the top left of the screen
canvas.drawBitmap(sprite, 0, 0, null);
//Draw the rotated right sprite on the 2nd row
canvas.drawBitmap(rSprite, 0, sprite.getHeight() + 5, null);
//Draw the rotated left sprite on the 3rd row
canvas.drawBitmap(lSprite, 0, sprite.getHeight() * 2 + 5, null);
}
}
}
use this code hope it will be helpful...
you must have to write this method to do rotate operation
public void paintFromCenter(float angle, Canvas c) {
Bitmap b = sprite;
Bitmap h = b;
Matrix matrix = new Matrix();
matrix.postRotate(angle, h.getWidth() / 2, h.getHeight());
matrix.postTranslate(getX(), getY());
// canvas.drawBitmap(bitmap, matrix, new Paint());
Bitmap bmp2 = Bitmap.createBitmap(h, 0, 0, frameWidth, frameHeight,
matrix, true);
c.drawBitmap(h, matrix, null);
}
in your program you have to write onTouchEvent() method
public boolean onTouchEvent(MotionEvent event) {
int action = event.getAction();
if (action == MotionEvent.ACTION_DOWN) {
edX = (int) event.getX();
edY = (int) event.getY();
if ((edX > objectSprite.getX()
&& edX < objectSprite.getX() + objectSprite.getWidth()
&& edY > objectSprite.getY() && edY < objectSprite.getY()
+ objectSprite.getHeight())) {
}
}
if (action == MotionEvent.ACTION_MOVE) {
emX = (int) event.getX();
emY = (int) event.getY();
if (edX < emX && angle <= 90) {
update(canvas);
CHAR = 'D';
} else if (edX > emX && angle > 0) {
update(canvas);
CHAR = 'U';
}
if (edY < emY && angle <= 90) {
update(canvas);
CHAR = 'L';
} else if (edY > emY && angle >= 0) {
update(canvas);
CHAR = 'R';
}
}
return true;
}
and you have to create update() method to rotate your angle on touch event angle can be define as your choice. Initially i have declare
int angle=1;
public void update(Canvas canvas) {
switch (CHAR) {
case 'D':
angle += 1;
break;
case 'U':
angle -= 1;
break;
case 'R':
angle -= 1;
break;
case 'L':
angle += 1;
break;
}
}
Now you have to draw your object in draw() method like this
public void draw() {
objectSprite.paintFromCenter(angle, canvas);
}
You just add this simple code to your button
imVCature_pic.setRotation(imVCature_pic.getRotation() + 90);
Matrix mat = new Matrix();
mat.preRotate(angle);///in degree
Bitmap mBitmap = Bitmap.createBitmap(originalBmp, 0, 0, modWidth, modHeight, mat, true);
//originalBmp -> original img as bitmap
//modHeight -> new height
//modWidth -> new width
use the above code.