I'm writting a 2d game in Iphone, which uses textures as sprites, I'm getting colored noise around some of the images I render ( but such noise never appears over the texture Itself, only in the transparent portion around It). The problem does not happen with the rest of my textures. This is the code I use to load textures:
- (void)loadTexture:(NSString*)nombre {
CGImageRef textureImage = [UIImage imageNamed:nombre].CGImage;
if (textureImage == nil) {
NSLog(#"Failed to load texture image");
return;
}
textureWidth = NextPowerOfTwo(CGImageGetWidth(textureImage));
textureHeight = NextPowerOfTwo(CGImageGetHeight(textureImage));
imageSizeX= CGImageGetWidth(textureImage);
imageSizeY= CGImageGetHeight(textureImage);
GLubyte *textureData = (GLubyte *)malloc(textureWidth * textureHeight * 4);
CGContextRef textureContext = CGBitmapContextCreate(textureData, textureWidth,textureHeight,8, textureWidth * 4,CGImageGetColorSpace(textureImage),kCGImageAlphaPremultipliedLast);
CGContextDrawImage(textureContext, CGRectMake(0.0, 0.0, (float)textureWidth, (float)textureHeight), textureImage);
CGContextRelease(textureContext);
glGenTextures(1, &textures[0]);
glBindTexture(GL_TEXTURE_2D, textures[0]);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, textureWidth, textureHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE, textureData);
free(textureData);
glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
glEnable(GL_BLEND);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
}
Your memory is not zeroed out before you draw the image in it. The funny pixels you see is old data in the transparent regions of your image. Use calloc instead of malloc (calloc returns zeroed memory).
You can also use CGContextSetBlendMode(textureContext, kCGBlendModeCopy); before drawing the image.
If you want to know the whole story:
This problem exists only for small images due to the fact that malloc has different code paths for small allocation sizes. It returns a small block from a pool it manages in user space. If the requested size is larger than a certain threshold (16K, I believe), malloc gets the memory from the kernel. The new pages are of course zeroed out.
It took me a while to figure that out.
Related
How can I rewrite Apple's GLCameraRipple example so that it doesn't require iOS 5.0?
I need to have it run on iOS 4.x, so I cannot use CVOpenGLESTextureCacheCreateTextureFromImage. What should I do?
As a follow on, I'm using the code below to provide YUV data rather than RGB, but the picture is not right, the screen is green. It seems as though UV plane doesn't work.
CVPixelBufferLockBaseAddress(cameraFrame, 0);
int bufferHeight = CVPixelBufferGetHeight(cameraFrame);
int bufferWidth = CVPixelBufferGetWidth(cameraFrame);
// Create a new texture from the camera frame data, display that using the shaders
glActiveTexture(GL_TEXTURE0);
glGenTextures(1, &_lumaTexture);
glBindTexture(GL_TEXTURE_2D, _lumaTexture);
glUniform1i(UNIFORM[Y], 0);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// This is necessary for non-power-of-two textures
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, bufferWidth, bufferHeight, 0, GL_LUMINANCE,
GL_UNSIGNED_BYTE, CVPixelBufferGetBaseAddressOfPlane(cameraFrame, 0));
glActiveTexture(GL_TEXTURE1);
glGenTextures(1, &_chromaTexture);
glBindTexture(GL_TEXTURE_2D, _chromaTexture);
glUniform1i(UNIFORM[UV], 1);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// This is necessary for non-power-of-two textures
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
// Using BGRA extension to pull in video frame data directly
glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE_ALPHA, bufferWidth/2, bufferHeight/2, 0, GL_LUMINANCE_ALPHA,
GL_UNSIGNED_BYTE, CVPixelBufferGetBaseAddressOfPlane(cameraFrame, 1));
[self drawFrame];
glDeleteTextures(1, &_lumaTexture);
glDeleteTextures(1, &_chromaTexture);
CVPixelBufferUnlockBaseAddress(cameraFrame, 0);
How can I fix this?
If you switch the pixel format from kCVPixelFormatType_420YpCbCr8BiPlanarFullRange to kCVPixelFormatType_32BGRA (at line 315 of RippleViewController) then captureOutput:didOutputSampleBuffer:fromConnection: will receive a sample buffer in which the image buffer can be uploaded straight to OpenGL via glTexImage2D (or glTexSubImage2D if you want to keep your texture sized as a power of two). That works because all iOS devices to date support the GL_APPLE_texture_format_BGRA8888 extension, allowing you to specify an otherwise non-standard format of GL_BGRA.
So you'd create a texture somewhere in advance with glGenTextures and replace line 235 with something like:
glBindTexture(GL_TEXTURE_2D, myTexture);
CVPixelBufferLockBaseAddress(pixelBuffer);
glTexSubImage2D(GL_TEXTURE_2D, 0,
0, 0,
CVPixelBufferGetWidth(pixelBuffer), CVPixelBufferGetHeight(pixelBuffer),
GL_BGRA, GL_UNSIGNED_BYTE,
CVPixelBufferGetBaseAddress(pixelBuffer));
CVPixelBufferUnlockBaseAddress(pixelBuffer);
You may want to check that the result of CVPixelBufferGetBytesPerRow is four times the result of CVPixelBufferGetWidth; I'm uncertain from the documentation whether it's guaranteed always to be (which, pragmatically, probably means that it isn't), but as long as it's a multiple of four you can just supply CVPixelBufferGetBytesPerRow divided by four as your pretend width, given that you're uploading a sub image anyway.
EDIT: in response to the follow-on question posted below as a comment, if you wanted to stick with receiving frames and making them available to the GPU in YUV then the code becomes visually ugly because what you're returned is a structure pointing to the various channel components but you'd want something like this:
// lock the base address, pull out the struct that'll show us where the Y
// and CbCr information is actually held
CVPixelBufferLockBaseAddress(pixelBuffer);
CVPlanarPixelBufferInfo_YCbCrBiPlanar *info = CVPixelBufferGetBaseAddress(imageBuffer);
// okay, upload Y. You'll want to communicate this texture to the
// SamplerY uniform within the fragment shader.
glBindTexture(GL_TEXTURE_2D, yTexture);
uint8_t *yBaseAddress = (uint8_t *)info + EndianU32_BtoN(info->componentInfoY.offset);
uint32_t yRowBytes = EndianU32_BtoN(info->componentInfoY.rowBytes);
/* TODO: check that yRowBytes is equal to CVPixelBufferGetWidth(pixelBuffer);
otherwise you'll need to shuffle memory a little */
glTexSubImage2D(GL_TEXTURE_2D, 0,
0, 0,
CVPixelBufferGetWidth(pixelBuffer), CVPixelBufferGetHeight(pixelBuffer),
GL_LUMINANCE, GL_UNSIGNED_BYTE,
yBaseAddress);
// we'll also need to upload the CbCr part of the buffer, as a two-channel
// (ie, luminance + alpha) texture. This texture should be supplied to
// the shader for the SamplerUV uniform.
glBindTexture(GL_TEXTURE_2D, uvTexture);
uint8_t *uvBaseAddress = (uint8_t *)info + EndianU32_BtoN(info->componentInfoCbCr.offset);
uint32_t uvRowBytes = EndianU32_BtoN(info->componentInfoCbCr.rowBytes);
/* TODO: a check on uvRowBytes, as above */
glTexSubImage2D(GL_TEXTURE_2D, 0,
0, 0,
CVPixelBufferGetWidth(pixelBuffer)/2, CVPixelBufferGetHeight(pixelBuffer)/2,
GL_LUMINANCE_ALPHA, GL_UNSIGNED_BYTE,
uvBaseAddress);
CVPixelBufferUnlockBaseAddress(pixelBuffer);
The iOS 5.0 fast texture upload capabilities can make for very fast uploading of camera frames and extraction of texture data, which is why Apple uses them in their latest sample code. For camera data, I've seen 640x480 frame upload times go from 9 ms to 1.8 ms using these iOS 5.0 texture caches on an iPhone 4S, and for movie capturing I've seen more than a fourfold improvement when switching to them.
That said, you still might want to provide a fallback for stragglers who have not yet updated to iOS 5.x. I do this in my open source image processing framework by using a runtime check for the texture upload capability:
+ (BOOL)supportsFastTextureUpload;
{
return (CVOpenGLESTextureCacheCreate != NULL);
}
If this returns NO, I use the standard upload process that we have had since iOS 4.0:
CVImageBufferRef cameraFrame = CMSampleBufferGetImageBuffer(sampleBuffer);
int bufferWidth = CVPixelBufferGetWidth(cameraFrame);
int bufferHeight = CVPixelBufferGetHeight(cameraFrame);
CVPixelBufferLockBaseAddress(cameraFrame, 0);
glBindTexture(GL_TEXTURE_2D, outputTexture);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, bufferWidth, bufferHeight, 0, GL_BGRA, GL_UNSIGNED_BYTE, CVPixelBufferGetBaseAddress(cameraFrame));
// Do your OpenGL ES rendering here
CVPixelBufferUnlockBaseAddress(cameraFrame, 0);
GLCameraRipple has one quirk in its upload process, and that is the fact that it uses YUV planar frames (split into Y and UV images), instead of one BGRA image. I get pretty good performance from my BGRA uploads, so I haven't seen the need to work with YUV data myself. You could either modify GLCameraRipple to use BGRA frames and the above code, or rework what I have above into YUV planar data uploads.
I have an iPhone game that uses images to display things such as buttons on screen to control the game. The images aren't huge, but I want to load them "lazily" and unload them from memory when they are not being used.
I have a function that loads images as follows:
void loadImageRef(NSString *name, GLuint location, CGImageRef *textureImage)
{
*textureImage = [UIImage imageNamed:name].CGImage;
if (*textureImage == nil) {
NSLog(#"Failed to load texture image");
return;
}
NSInteger texWidth = CGImageGetWidth(*textureImage);
NSInteger texHeight = CGImageGetHeight(*textureImage);
GLubyte *textureData = (GLubyte *)malloc(texWidth * texHeight * 4);
CGContextRef textureContext = CGBitmapContextCreate(textureData,
texWidth, texHeight,
8, texWidth * 4,
CGImageGetColorSpace(*textureImage),
kCGImageAlphaPremultipliedLast);
CGContextTranslateCTM(textureContext, 0, texHeight);
CGContextScaleCTM(textureContext, 1.0, -1.0);
CGContextDrawImage(textureContext, CGRectMake(0.0, 0.0, (float)texWidth, (float)texHeight), *textureImage);
CGContextRelease(textureContext);
glBindTexture(GL_TEXTURE_2D, location);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, texWidth, texHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE, textureData);
free(textureData);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
}
The reason I pass the CGImageRef to the function is so that I can free it later. But I don't know if this is the correct thing to do?
I call the function as follows (for example):
loadImageRef(#"buttonConfig.png", textures[IMG_CONFIG], &imagesRef[IMG_CONFIG]);
And when I'm finished with it I unload it as follows:
unloadImage(&imagesRef[IMG_CONFIG]);
which calls the function:
void unloadImage(CGImageRef *image)
{
CGImageRelease(*image);
}
But when I run the app, I get EXC_BAD_ACCESS error, either when unloading, or loading for the second time (i.e. when it is needed again). I don't see anything else to help determine the real cause of the problem.
Perhaps I am attacking this issue from the wrong angle. What is the usual method of lazy loading of images, and what is the usual way to unload the image to free up the memory?
Many thanks in advance,
Sam
You should avoid using the [UIImage imageNamed:name] method at all costs if you want to ensure things don't stay cached. imageNamed caches all images it pulls through. You want to use
UIImage *image = [[UIImage alloc] initWithContentsOfFile:[[NSBundle mainBundle] pathForResource:fileNameWithoutExtension ofType:fileNameExtension]];
With that, you can simply release the object when you are done with it and free the memory.
Apple has improved caching with [UIImage imageNamed:] but it still isn't on demand.
I have a simple 16x16 particle that goes from being opaque to transparent. Unfortunately is appears different in my iPhone port and I can't see where the differences in the code are. Most of the code is essentially the same.
I've uploaded an image to here to show the problem
The particle on the left is the incorrectly rendered iPhone version and the right is how it appears on Mac and Windows. It's just a simple RGBA .png file.
I've tried numerous blend functions and glTexEnv setting but I can't seem to make them the same.
Just to be thorough, my Texture loading code on the iPhone looks like the following
GLuint TextureLoader::LoadTexture(const char *path)
{
NSString *macPath = [NSString stringWithCString:path length:strlen(path)];
GLuint texture = 0;
CGImageRef textureImage = [UIImage imageNamed:macPath].CGImage;
if (textureImage == nil)
{
NSLog(#"Failed to load texture image");
return 0;
}
NSInteger texWidth = CGImageGetWidth(textureImage);
NSInteger texHeight = CGImageGetHeight(textureImage);
GLubyte *textureData = new GLubyte[texWidth * texHeight * 4];
memset(textureData, 0, texWidth * texHeight * 4);
CGContextRef textureContext = CGBitmapContextCreate(textureData, texWidth, texHeight, 8, texWidth * 4, CGImageGetColorSpace(textureImage), kCGImageAlphaPremultipliedLast);
CGContextDrawImage(textureContext, CGRectMake(0.0, 0.0, (float)texWidth, (float)texHeight), textureImage);
CGContextRelease(textureContext);
//Make a texture ID, bind it, create it
glGenTextures(1, &texture);
glBindTexture(GL_TEXTURE_2D, texture);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, texWidth, texHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE, textureData);
delete[] textureData;
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
return texture;
}
The blend function I use is glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
I'll try any ideas people throw at me, because this has been a bit of a mystery to me.
Cheers.
this looks like the standard "textures are converted to premultiplied alpha" problem.
you can use
glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
or you can write custom loading code to avoid the premultiplication.
Call me naive, but seeing that premultiplying an image requires (ar, ag, a*b, a), I figured I'd just divide the rgb values by a.
Of course as soon as the alpha value is larger than the r, g, b components, the particle texture became black. Oh well. Unless I can find a different image loader to the one above, then I'll just make all the rgb components 0xff (white). This is a good temporary solution for me because I either need a white particle or just colourise it in the application. Later on I might just make raw rgba files and read them in, because this is mainly for very small 16x16 and smaller particle textures.
I can't use Premultiplied textures for the particle system because overlapping multiple particle textures saturates the colours way too much.
Using a couple of posts here in StackOverflow, I created what is supposed to be a simple render-to-texture using a framebuffer.
The problem here is that it's not working. Something is broken in the mix, as my final texture is just a white square. I am not getting any gl errors whatsoever. Here is my code.
Declare instance variables.
GLuint texture;
GLuint textureFrameBuffer;
Generate the texture and framebuffer.
glGetError();
//Generate the texture that we will draw to (saves us a lot of processor).
glEnable(GL_TEXTURE_2D);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
// Use OpenGL ES to generate a name for the texture.
// Pass by reference so that our texture variable gets set.
glGenTextures(1, &texture);
// Bind the texture name.
glBindTexture(GL_TEXTURE_2D, texture);
// Specify a 2D texture image, providing a pointer to the image data in memory.
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 512, 128, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
//Create a frame buffer to draw to. This will allow us to directly edit the texture.
GLint oldFBO;
glGetIntegerv(GL_FRAMEBUFFER_BINDING_OES, &oldFBO);
glGenFramebuffersOES(1, &textureFrameBuffer);
glBindFramebufferOES(GL_FRAMEBUFFER_OES, textureFrameBuffer);
glFramebufferTexture2DOES(GL_FRAMEBUFFER_OES, GL_COLOR_ATTACHMENT0_OES, GL_TEXTURE_2D, texture, 0);
glBindFramebufferOES(GL_FRAMEBUFFER_OES, oldFBO);
GLenum err = glGetError();
if (err != GL_NO_ERROR)
{
NSLog(#"Error on framebuffer init. glError: 0x%04X", err);
}
Draw a big string into the framebuffer.
glGetError();
GLint oldFBO;
glGetIntegerv(GL_FRAMEBUFFER_BINDING_OES, &oldFBO);
//Bind our frame buffer.
glBindFramebufferOES(GL_FRAMEBUFFER_OES, textureFrameBuffer);
//Clear out the texture.
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
//Draw the letters to the frame buffer. (calls glDrawArrays a bunch of times, binds various textures, etc.) Does everything in 2D.
[self renderDialog:displayString withSprite:displaySprite withName:displaySpriteName];
//Unbind the frame buffer.
glBindFramebufferOES(GL_FRAMEBUFFER_OES, oldFBO);
GLenum err = glGetError();
if (err != GL_NO_ERROR)
{
NSLog(#"Error on string creation. glError: 0x%04X", err);
}
Draw it.
glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
glGetError();
//Draw the text.
[EAGLView enable2D];
//Push the matrix so we can keep it as it was previously.
glPushMatrix();
//Store the coordinates/dimensions from the rectangle.
float x = 0;
float y = [Globals getPlayableHeight] - dialogRect.size.height;
float w = [Globals getPlayableWidth];
float h = dialogRect.size.height;
// Set up an array of values to use as the sprite vertices.
GLfloat vertices[] =
{
x, y,
x, y+h,
x+w, y+h,
x+w, y
};
// Set up an array of values for the texture coordinates.
GLfloat texcoords[] =
{
0, 0,
0, h / 128,
w / 512, h / 128,
w / 512, 0
};
//Render the vertices by pointing to the arrays.
glVertexPointer(2, GL_FLOAT, 0, vertices);
glTexCoordPointer(2, GL_FLOAT, 0, texcoords);
// Set the texture parameters to use a linear filter when minifying.
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
//Allow transparency and blending.
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
//Enable 2D textures.
glEnable(GL_TEXTURE_2D);
//Bind this texture.
[EAGLView bindTexture:texture];
//Finally draw the arrays.
glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
//Restore the model view matrix to prevent contamination.
glPopMatrix();
GLenum err = glGetError();
if (err != GL_NO_ERROR)
{
NSLog(#"Error on draw. glError: 0x%04X", err);
}
Any external things I called work just fine in other contexts. Any ideas? I know almost nothing about framebuffers, so any help troubleshooting would be great.
Texture parameters are set on a per-texture basis. The code you posted appears to be setting GL_TEXTURE_MIN_FILTER before the texture you’re rendering to has been created or bound. If you’re not setting the filter anywhere else, and you haven’t specified texture images for the remaining levels, your texture is likely incomplete, which is why you’re getting white.
For future reference, the absence of GL errors after framebuffer setup does not mean that the framebuffer is usable for rendering. You should also check that the framebuffer is complete by calling glCheckFramebufferStatusOES(GL_FRAMEBUFFER_OES) and verifying that GL_FRAMEBUFFER_COMPLETE_OES is returned.
Here's the code I use to load a texture. image is a CGImageRef. After loading the image with this code, I eventually draw the image with glDrawArrays().
size_t imageW = CGImageGetWidth(image);
size_t imageH = CGImageGetHeight(image);
size_t picSize = pow2roundup((imageW > imageH) ? imageW : imageH);
GLubyte *textureData = (GLubyte *) malloc(picSize * picSize << 2);
CGContextRef imageContext = CGBitmapContextCreate( textureData, picSize, picSize, 8, picSize << 2, CGImageGetColorSpace(image), kCGImageAlphaNoneSkipLast | kCGBitmapByteOrder32Big );
if (imageContext != NULL) {
CGContextDrawImage(imageContext, CGRectMake(0.0, 0.0, (CGFloat)imageW, (CGFloat)imageH), image);
glGenTextures(1, &textureId);
glBindTexture(GL_TEXTURE_2D, textureId);
// when texture area is small, bilinear filter the closest mipmap
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
// when texture area is large, bilinear filter the original
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// the texture wraps over at the edges (repeat)
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, picSize, picSize, 0, GL_RGBA, GL_UNSIGNED_BYTE, textureData);
GLenum err = glGetError();
if (err != GL_NO_ERROR)
NSLog(#"Error uploading texture. glError: 0x%04X", err);
CGContextRelease(imageContext);
}
free(textureData);
This seems to work fine when the image is 320x480, but it fails when the image is larger (for example, picSize = 2048).
Here's what I get in the Debugger Console:
Error uploading texture. glError: 0x0501
What's the meaning of this error? What's the best workaround?
Aren’t you simply hitting the maximum texture size limit? The error code is GL_INVALID_VALUE, see the glTexImage2D docs:
GL_INVALID_VALUE is generated if width
or height is less than 0 or greater
than 2 + GL_MAX_TEXTURE_SIZE, or if
either cannot be represented as
2k+2(border) for some integer value of
k.
iPhone does not support textures larger than 1024 pixels. The workaround is to split the image into several textures.
Maybe you are simply running out of memory - did you verify the value returned from malloc() is not NULL?
(this could explain getting 0x0501, which is GL_INVALID_VALUE).
I also experienced the same kind of issue with GLKitBaseEffect, it seemed to be a memory issue (as Hexagon proposed). To fix this, I had to add manual texture release calls:
GLuint name = self.texture.name;
glDeleteTextures(1, &name);
See this thread for more: Release textures (GLKTextureInfo objects) allocated by GLKTextureLoader.