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POTexture mapping problem in OpenGLES
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copied!<p>I'm very new to OpenGL and I'm using managed OpenGLES wrapper written for Windows Mobile phones (<a href="http://www.koushikdutta.com/2008/08/net-compact-framework-wrapper-for.html" rel="nofollow noreferrer">OpenGLES Windows Mobile</a>). I have a simple task of drawing a square (got that) and texturing it with an image from the disk, so I basically just want to display a jpg file on the screen. However every time I try to do it, I get a white square displayed, with no texture. I verified that my texture loads correctly (using some of the existing examples, and just replacing texture with mine). So I think my problem is correctly mapping texture to the object. Here's my code (functions and objects removed to make it simple):</p> <pre><code> private Bitmap image = new Bitmap(@"\Storage Card\someimage.jpg"); using (MemoryStream ms = new MemoryStream()) { Image.Save(ms, System.Drawing.Imaging.ImageFormat.Bmp); myImage = Texture.LoadStream(ms, false); } gl.ShadeModel(gl.GL_SMOOTH); gl.ClearColor(0.0f, 0.0f, 0.0f, 0.5f); gl.BlendFunc(gl.GL_SRC_ALPHA, gl.GL_ONE_MINUS_SRC_ALPHA); gl.Hint(gl.GL_PERSPECTIVE_CORRECTION_HINT, gl.GL_NICEST); glLocation.Clear(); gl.Clear(gl.GL_COLOR_BUFFER_BIT); gl.MatrixMode(gl.GL_PROJECTION); gl.LoadIdentity(); gl.Orthof(0, ClientSize.Width, ClientSize.Height, 0, 0, 1); gl.Disable(gl.GL_DEPTH_TEST); gl.MatrixMode(gl.GL_MODELVIEW); gl.LoadIdentity(); float[] rectangle = new float[] { 0, 0, myImage.Width, 0, 0, myImage.Height, myImage.Width, myImage.Height }; float[] texturePosition = new float[] { 0, 0, myImage.Width, 0, 0, myImage.Height, myImage.Width, myImage.Height }; //Bind texture gl.BindTexture(gl.GL_TEXTURE_2D, myImage.Name); gl.TexParameteri(gl.GL_TEXTURE_2D, gl.GL_TEXTURE_MIN_FILTER, gl.GL_LINEAR); gl.TexParameteri(gl.GL_TEXTURE_2D, gl.GL_TEXTURE_MAG_FILTER, gl.GL_LINEAR); //move cursor glLocation.MoveCursor(Location.X, Location.Y); gl.EnableClientState(gl.GL_TEXTURE_COORD_ARRAY); gl.EnableClientState(gl.GL_VERTEX_ARRAY); //draw square and texture it. fixed (float* rectanglePointer = &rectangle[0], positionPointer = &texturePosition[0]) { gl.TexCoordPointer(2, gl.GL_FLOAT, 0, (IntPtr)positionPointer); gl.VertexPointer(2, gl.GL_FLOAT, 0, (IntPtr)rectanglePointer); gl.DrawArrays(gl.GL_TRIANGLE_STRIP, 0, 4); } gl.DisableClientState(gl.GL_TEXTURE_COORD_ARRAY); gl.DisableClientState(gl.GL_VERTEX_ARRAY); egl.SwapBuffers(myDisplay, mySurface); gl.Clear(gl.GL_COLOR_BUFFER_BIT); </code></pre>

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