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POTrying selectively redraw background for an android game, but the moving image is duplicated across the screen
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copied!<p>It's easiest if I just start by showing pictures of the problem. The pictures show a snapshot of a texture moving around.</p> <p>The application on my HTC Hero:</p> <p><img src="https://i.stack.imgur.com/h6dBC.png" alt="Image from my Hero"></p> <p>The same application on the emulator where it works fine (Disregard the randomly placed leftovers, I know the cause of them, and it's not a problem): <img src="https://i.stack.imgur.com/wGomb.png" alt="Image from the emulator"></p> <p>Now, if you look at the first image, the top one is the "real one" and the others always follow beneath, and there are copies above aswell. I am currently only repainting the background squares that was visited, and they are for some reason drawn above the copies (you can see they are all partially painted over by a tile).</p> <p>Do you have to always repaint the whole screen every frame on the android phones? Or is it possible to get rid of these weird copies?</p> <p>Here is the code used to draw the textures (I'm new to opengl-es so it's a lot like replica island):</p> <p>first</p> <pre><code>public static void beginDrawing(GL10 gl, float viewWidth, float viewHeight) { gl.glShadeModel(GL10.GL_FLAT); gl.glEnable(GL10.GL_BLEND); gl.glBlendFunc(GL10.GL_ONE, GL10.GL_ONE_MINUS_SRC_ALPHA); gl.glColor4x(0x10000, 0x10000, 0x10000, 0x10000); gl.glMatrixMode(GL10.GL_PROJECTION); gl.glPushMatrix(); gl.glLoadIdentity(); gl.glOrthof(0.0f, viewWidth, 0.0f, viewHeight, 0.0f, 1.0f); gl.glMatrixMode(GL10.GL_MODELVIEW); gl.glPushMatrix(); gl.glLoadIdentity(); gl.glEnable(GL10.GL_TEXTURE_2D); } </code></pre> <p>Then for every texture (I draw background first, then in this case only one hulk texture. I'm sure it's being drawn only once):</p> <pre><code> gl.glBindTexture(GL10.GL_TEXTURE_2D, textureID); ((GL11Ext) gl).glDrawTexfOES(x, y, 0, (float) mWidth, (float) mHeight); </code></pre> <p>and at the end:</p> <pre><code>public static void endDrawing(GL10 gl) { gl.glDisable(GL10.GL_BLEND); gl.glMatrixMode(GL10.GL_PROJECTION); gl.glPopMatrix(); gl.glMatrixMode(GL10.GL_MODELVIEW); gl.glPopMatrix(); } </code></pre> <p>The code I use to load textures:</p> <pre><code>private void loadGLTextures(GL10 gl) { int[] textures = new int[1]; gl.glGenTextures(1, textures, 0); textureID = textures[0]; gl.glBindTexture(GL10.GL_TEXTURE_2D, textureID); 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); gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_S, GL10.GL_CLAMP_TO_EDGE); gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_T, GL10.GL_CLAMP_TO_EDGE); gl.glTexEnvf(GL10.GL_TEXTURE_ENV, GL10.GL_TEXTURE_ENV_MODE, GL10.GL_MODULATE); GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmap, 0); int[] mCropWorkspace = new int[4]; mCropWorkspace[0] = 0; mCropWorkspace[1] = bitmap.getHeight(); mCropWorkspace[2] = bitmap.getWidth(); mCropWorkspace[3] = -bitmap.getHeight(); ((GL11) gl).glTexParameteriv(GL10.GL_TEXTURE_2D, GL11Ext.GL_TEXTURE_CROP_RECT_OES, mCropWorkspace, 0); mCrop = mCropWorkspace; bitmap.recycle(); } </code></pre> <p>All help is very much appriciated, and please leave a comment if anything is unclear!</p> <p>EDIT: I should add that if I every frame redraw all the squares, the "extra" images are hidden, and it works the way it should.</p>

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