I concur with this as well from experience. Non powers of 2 textures are supported by some implementations on some devices, but to be safe, always use powers of 2 textures. In your case if you want to draw something that is 180x140, just draw that part of the texture, while having the full texture you load be a power of two (256x256 would be the minimum enclosing size, as has been suggested by others here).
handy chart for you, though us computer geeks should know these cold! :) http://www.vaughns-1-pagers.com/computer/powers-of-2.htm On Monday, October 3, 2011 11:56:06 AM UTC-4, latimerius wrote: > > In my experience, the classic cause of "white" textures on some hardware > but not other is a non-power-of-two texture. Your code doesn't seem to > enforce POT texture dimensions, are your assets POT? > > On Mon, Oct 3, 2011 at 5:43 PM, saex <[email protected]> wrote: > >> i have an app that draws a square on the screen with a texture, and >> the user can rotate the square touching the screen. It works fine with >> android 1.5 to 2.1. But when i test the App on a Motorola Droid with >> android 2.2.2 something is failing because the square is loaded with a >> white texture. >> >> What is wrong? >> >> This is the code of my class square: >> >> public class Square { >> >> /** The buffer holding the vertices */ >> private FloatBuffer vertexBuffer; >> /** The buffer holding the texture coordinates */ >> private FloatBuffer textureBuffer; >> /** Our texture pointer */ >> private int[] textures = new int[3]; >> >> /** The initial vertex definition */ >> private float vertices[] = { >> -1.0f, -1.0f, 0.0f, >> //Bottom Left >> 1.0f, -1.0f, 0.0f, >> //Bottom Right >> -1.0f, 1.0f, 0.0f, >> //Top Left >> 1.0f, 1.0f, 0.0f >> //Top Right >> >> }; >> /** The initial texture coordinates (u, v) */ >> >> private float texture[] = { >> //Mapping coordinates for the >> vertices >> 0.0f, 0.0f, >> 0.0f, 1.0f, >> 1.0f, 0.0f, >> 1.0f, 1.0f >> }; >> >> /** >> * The Square constructor. >> * >> * Initiate the buffers. >> */ >> public Square() { >> // >> ByteBuffer byteBuf = >> ByteBuffer.allocateDirect(vertices.length * 4); >> byteBuf.order(ByteOrder.nativeOrder()); >> vertexBuffer = byteBuf.asFloatBuffer(); >> vertexBuffer.put(vertices); >> vertexBuffer.position(0); >> // >> byteBuf = ByteBuffer.allocateDirect(texture.length * 4); >> byteBuf.order(ByteOrder.nativeOrder()); >> textureBuffer = byteBuf.asFloatBuffer(); >> textureBuffer.put(texture); >> textureBuffer.position(0); >> } >> >> /** >> * The object own drawing function. >> * Called from the renderer to redraw this instance >> * with possible changes in values. >> * >> * @param gl - The GL Context >> */ >> public void draw(GL10 gl) { >> //Set the face rotation >> //gl.glFrontFace(GL10.GL_CW); >> gl.glFrontFace(GL10.GL_CCW); >> //Bind our only previously generated texture in this case >> gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[0]); >> //Point to our vertex buffer >> gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer); >> gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, textureBuffer); >> //Enable vertex buffer >> gl.glEnableClientState(GL10.GL_VERTEX_ARRAY); >> gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY); >> //Set The Color To Blue >> //gl.glColor4f(0.5f, 0.5f, 1.0f, 1.0f); >> //Draw the vertices as triangle strip >> gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, 0, vertices.length >> / 3); >> //Disable the client state before leaving >> gl.glDisableClientState(GL10.GL_VERTEX_ARRAY); >> gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY); >> >> /// >> //Bind the texture according to the set texture filter >> //gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[filter]); >> } >> >> /** >> * Load the textures >> * >> * @param gl - The GL Context >> * @param context - The Activity context >> */ >> public void loadGLTexture(GL10 gl, Context context) { >> //Generate one texture pointer... >> gl.glGenTextures(1, textures, 0); >> //...and bind it to our array >> gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[0]); >> //Create Nearest Filtered Texture >> gl.glTexParameterf(GL10.GL_TEXTURE_2D, >> GL10.GL_TEXTURE_MIN_FILTER, >> GL10.GL_NEAREST); >> gl.glTexParameterf(GL10.GL_TEXTURE_2D, >> GL10.GL_TEXTURE_MAG_FILTER, >> GL10.GL_LINEAR); >> >> //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); >> >> //Get the texture from the Android resource directory >> InputStream is = >> context.getResources().openRawResource(R.drawable.radiocd2); >> Bitmap bitmap = null; >> try { >> //BitmapFactory is an Android graphics utility for >> images >> bitmap = BitmapFactory.decodeStream(is); >> >> } finally { >> //Always clear and close >> try { >> is.close(); >> is = null; >> } catch (IOException e) { >> } >> } >> >> //Use the Android GLUtils to specify a two-dimensional >> texture image >> from our bitmap >> GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmap, 0); >> >> /* >> * This is a change to the original tutorial, as >> buildMipMap does >> not exist anymore >> * in the Android SDK. >> * >> * We check if the GL context is version 1.1 and generate >> MipMaps by >> flag. >> * Otherwise we call our own buildMipMap implementation >> */ >> if(gl instanceof GL11) { >> gl.glTexParameterf(GL11.GL_TEXTURE_2D, >> GL11.GL_GENERATE_MIPMAP, >> GL11.GL_TRUE); >> GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmap, >> 0); >> >> // >> } else { >> buildMipmap(gl, bitmap); >> } >> >> //Clean up >> bitmap.recycle(); >> } >> >> /** >> * Our own MipMap generation implementation. >> * Scale the original bitmap down, always by factor two, >> * and set it as new mipmap level. >> * >> * Thanks to Mike Miller (with minor changes)! >> * >> * @param gl - The GL Context >> * @param bitmap - The bitmap to mipmap >> */ >> private void buildMipmap(GL10 gl, Bitmap bitmap) { >> // >> int level = 0; >> // >> int height = bitmap.getHeight(); >> int width = bitmap.getWidth(); >> >> // >> while(height >= 1 || width >= 1) { >> //First of all, generate the texture from our >> bitmap and set it to >> the according level >> GLUtils.texImage2D(GL10.GL_TEXTURE_2D, level, >> bitmap, 0); >> >> // >> if(height == 1 || width == 1) { >> break; >> } >> >> //Increase the mipmap level >> level++; >> >> // >> height /= 2; >> width /= 2; >> Bitmap bitmap2 = Bitmap.createScaledBitmap(bitmap, >> width, height, >> true); >> >> //Clean up >> bitmap.recycle(); >> bitmap = bitmap2; >> } >> } >> } >> >> -- >> You received this message because you are subscribed to the Google >> Groups "Android Developers" group. >> To post to this group, send email to [email protected] >> To unsubscribe from this group, send email to >> [email protected] >> For more options, visit this group at >> http://groups.google.com/group/android-developers?hl=en > > > -- You received this message because you are subscribed to the Google Groups "Android Developers" group. 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