AC3DTexture.m

/*

===== IMPORTANT =====

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Although this sample code has been reviewed for technical accuracy, it is not
final. Apple is supplying this information to help you plan for the adoption of
the technologies and programming interfaces described herein. This information
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versions of this sample code may be provided with future seeds of the API or
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=====================

File: AC3DTexture.m
Abstract: Convenience class that allows to create OpenGL 2D textures from
images, text or raw data.

Version: 1.1

Disclaimer: IMPORTANT:  This Apple software is supplied to you by Apple Inc.
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*/

#import <OpenGLES/ES1/glext.h>

#import "AC3DTexture.h"
#import "OpenGL_Internal.h"

//CONSTANTS:

#define kMaxTextureSize		1024

//CLASS IMPLEMENTATIONS:

@implementation AC3DTexture

@synthesize contentSize=_size, pixelFormat=_format, pixelsWide=_width, pixelsHigh=_height, name=_name, maxS=_maxS, maxT=_maxT;

- (id) initWithData:(const void*)data pixelFormat:(AC3DTexturePixelFormat)pixelFormat pixelsWide:(NSUInteger)width pixelsHigh:(NSUInteger)height contentSize:(CGSize)size
{
	GLint					saveName;
	
	if((self = [super init])) {
		glGenTextures(1, &_name);
		glGetIntegerv(GL_TEXTURE_BINDING_2D, &saveName);
		glBindTexture(GL_TEXTURE_2D, _name);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
		//glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST);
		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
		//glTexParameteri(GL_TEXTURE_2D, GL_GENERATE_MIPMAP, GL_TRUE);		
		//glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
		//glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
		switch(pixelFormat) {
			
			case kAC3DTexturePixelFormat_RGBA8888:
			glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, data);
			break;
			
			case kAC3DTexturePixelFormat_RGBA4444:
			glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_SHORT_4_4_4_4, data);
			break;
			
			case kAC3DTexturePixelFormat_RGBA5551:
			glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_SHORT_5_5_5_1, data);
			break;
			
			case kAC3DTexturePixelFormat_RGB565:
			glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_SHORT_5_6_5, data);
			break;
			
			case kAC3DTexturePixelFormat_RGB888:
			glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, data);
			break;
			
			case kAC3DTexturePixelFormat_L8:
			glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, width, height, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, data);
			break;
			
			case kAC3DTexturePixelFormat_A8:
			glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, width, height, 0, GL_ALPHA, GL_UNSIGNED_BYTE, data);
			break;
			
			case kAC3DTexturePixelFormat_LA88:
			glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE_ALPHA, width, height, 0, GL_LUMINANCE_ALPHA, GL_UNSIGNED_BYTE, data);
			break;
			
			case kAC3DTexturePixelFormat_RGB_PVRTC2:
			glCompressedTexImage2D(GL_TEXTURE_2D, 0, GL_COMPRESSED_RGB_PVRTC_2BPPV1_IMG, width, height, 0, (width * height) / 4, data);
			break;
			
			case kAC3DTexturePixelFormat_RGB_PVRTC4:
			glCompressedTexImage2D(GL_TEXTURE_2D, 0, GL_COMPRESSED_RGB_PVRTC_4BPPV1_IMG, width, height, 0, (width * height) / 2, data);
			break;
			
			case kAC3DTexturePixelFormat_RGBA_PVRTC2:
			glCompressedTexImage2D(GL_TEXTURE_2D, 0, GL_COMPRESSED_RGBA_PVRTC_2BPPV1_IMG, width, height, 0, (width * height) / 4, data);
			break;
			
			case kAC3DTexturePixelFormat_RGBA_PVRTC4:
			glCompressedTexImage2D(GL_TEXTURE_2D, 0, GL_COMPRESSED_RGBA_PVRTC_4BPPV1_IMG, width, height, 0, (width * height) / 2, data);
			break;
			
			default:
			[NSException raise:NSInternalInconsistencyException format:@""];
			
		}
		glBindTexture(GL_TEXTURE_2D, saveName);
		
		if(!CHECK_GL_ERROR()) {
			[self release];
			return nil;
		}
		
		_size = size;
		_width = width;
		_height = height;
		_format = pixelFormat;
		_maxS = size.width / (float)width;
		_maxT = size.height / (float)height;
	}
	
	return self;
}

- (void) dealloc
{
	if(_name)
	glDeleteTextures(1, &_name);
	
	[super dealloc];
}

- (NSString*) description
{
	return [NSString stringWithFormat:@"<%@ = %08X | Name = %i | Dimensions = %ix%i | Coordinates = (%.2f, %.2f)>", [self class], self, _name, _width, _height, _maxS, _maxT];
}

@end

@implementation AC3DTexture (Image)

- (id) initWithImagePath:(NSString*)path
{
	return [self initWithImagePath:path sizeToFit:NO];
}

- (id) initWithImagePath:(NSString*)path sizeToFit:(BOOL)sizeToFit
{
	return [self initWithImagePath:path sizeToFit:sizeToFit pixelFormat:kAC3DTexturePixelFormat_Automatic];
}

- (id) initWithImagePath:(NSString*)path sizeToFit:(BOOL)sizeToFit pixelFormat:(AC3DTexturePixelFormat)pixelFormat
{
	UIImage*				uiImage;
	NSString*				enterPath = path;
	
	if(![path isAbsolutePath])
		path = [[NSBundle mainBundle] pathForResource:path ofType:nil];
	
	uiImage = [[UIImage alloc] initWithContentsOfFile:path];
	self = [self initWithCGImage:[uiImage CGImage] orientation:[uiImage imageOrientation] sizeToFit:sizeToFit pixelFormat:pixelFormat];
	[uiImage release];
	
	if(self == nil)
		REPORT_ERROR(@"Failed loading image at path \"%@\"", enterPath);
	
	return self;
}
	
- (id) initWithCGImage:(CGImageRef)image orientation:(UIImageOrientation)orientation sizeToFit:(BOOL)sizeToFit pixelFormat:(AC3DTexturePixelFormat)pixelFormat
{
	NSUInteger				width,
							height,
							i;
	CGContextRef			context = nil;
	void*					data = nil;;
	CGColorSpaceRef			colorSpace;
	void*					tempData;
	unsigned char*			inPixel8;
	unsigned int*			inPixel32;
	unsigned char*			outPixel8;
	unsigned short*			outPixel16;
	BOOL					hasAlpha;
	CGImageAlphaInfo		info;
	CGAffineTransform		transform;
	CGSize					imageSize;
	
	if(image == NULL) {
		[self release];
		return nil;
	}
	
	if(pixelFormat == kAC3DTexturePixelFormat_Automatic) {
		info = CGImageGetAlphaInfo(image);
		hasAlpha = ((info == kCGImageAlphaPremultipliedLast) || (info == kCGImageAlphaPremultipliedFirst) || (info == kCGImageAlphaLast) || (info == kCGImageAlphaFirst) ? YES : NO);
		if(CGImageGetColorSpace(image)) {
			if(CGColorSpaceGetModel(CGImageGetColorSpace(image)) == kCGColorSpaceModelMonochrome) {
				if(hasAlpha) {
					pixelFormat = kAC3DTexturePixelFormat_LA88;
#if __DEBUG__
					if((CGImageGetBitsPerComponent(image) != 8) && (CGImageGetBitsPerPixel(image) != 16))
					REPORT_ERROR(@"Unoptimal image pixel format for image at path \"%@\"", path);
#endif
				}
				else {
					pixelFormat = kAC3DTexturePixelFormat_L8;
#if __DEBUG__
					if((CGImageGetBitsPerComponent(image) != 8) && (CGImageGetBitsPerPixel(image) != 8))
					REPORT_ERROR(@"Unoptimal image pixel format for image at path \"%@\"", path);
#endif
				}
			}
			else {
				if((CGImageGetBitsPerPixel(image) == 16) && !hasAlpha)
				pixelFormat = kAC3DTexturePixelFormat_RGBA5551;
				else {
					if(hasAlpha)
					pixelFormat = kAC3DTexturePixelFormat_RGBA8888;
					else {
						pixelFormat = kAC3DTexturePixelFormat_RGB565;
#if __DEBUG__
						if((CGImageGetBitsPerComponent(image) != 8) && (CGImageGetBitsPerPixel(image) != 24))
						REPORT_ERROR(@"Unoptimal image pixel format for image at path \"%s\"", path);
#endif
					}
				}
			}		
		}
		else { //NOTE: No colorspace means a mask image
			pixelFormat = kAC3DTexturePixelFormat_A8;
#if __DEBUG__
			if((CGImageGetBitsPerComponent(image) != 8) && (CGImageGetBitsPerPixel(image) != 8))
			REPORT_ERROR(@"Unoptimal image pixel format for image at path \"%@\"", path);
#endif
		}
	}
	
	imageSize = CGSizeMake(CGImageGetWidth(image), CGImageGetHeight(image));
	switch(orientation) {
		
		case UIImageOrientationUp: //EXIF = 1
		transform = CGAffineTransformIdentity;
		break;
		
		case UIImageOrientationUpMirrored: //EXIF = 2
		transform = CGAffineTransformMakeTranslation(imageSize.width, 0.0);
		transform = CGAffineTransformScale(transform, -1.0, 1.0);
		break;
		
		case UIImageOrientationDown: //EXIF = 3
		transform = CGAffineTransformMakeTranslation(imageSize.width, imageSize.height);
		transform = CGAffineTransformRotate(transform, M_PI);
		break;
		
		case UIImageOrientationDownMirrored: //EXIF = 4
		transform = CGAffineTransformMakeTranslation(0.0, imageSize.height);
		transform = CGAffineTransformScale(transform, 1.0, -1.0);
		break;
		
		case UIImageOrientationLeftMirrored: //EXIF = 5
		transform = CGAffineTransformMakeTranslation(imageSize.height, imageSize.width);
		transform = CGAffineTransformScale(transform, -1.0, 1.0);
		transform = CGAffineTransformRotate(transform, 3.0 * M_PI / 2.0);
		break;
		
		case UIImageOrientationLeft: //EXIF = 6
		transform = CGAffineTransformMakeTranslation(0.0, imageSize.width);
		transform = CGAffineTransformRotate(transform, 3.0 * M_PI / 2.0);
		break;
		
		case UIImageOrientationRightMirrored: //EXIF = 7
		transform = CGAffineTransformMakeScale(-1.0, 1.0);
		transform = CGAffineTransformRotate(transform, M_PI / 2.0);
		break;
		
		case UIImageOrientationRight: //EXIF = 8
		transform = CGAffineTransformMakeTranslation(imageSize.height, 0.0);
		transform = CGAffineTransformRotate(transform, M_PI / 2.0);
		break;
		
		default:
		[NSException raise:NSInternalInconsistencyException format:@"Invalid image orientation"];
		
	}
	if((orientation == UIImageOrientationLeftMirrored) || (orientation == UIImageOrientationLeft) || (orientation == UIImageOrientationRightMirrored) || (orientation == UIImageOrientationRight))
	imageSize = CGSizeMake(imageSize.height, imageSize.width);
	
	width = imageSize.width;
	if((width != 1) && (width & (width - 1))) {
		i = 1;
		while((sizeToFit ? 2 * i : i) < width)
		i *= 2;
		width = i;
	}
	height = imageSize.height;
	if((height != 1) && (height & (height - 1))) {
		i = 1;
		while((sizeToFit ? 2 * i : i) < height)
		i *= 2;
		height = i;
	}
	while((width > kMaxTextureSize) || (height > kMaxTextureSize)) {
#if __DEBUG__
		REPORT_ERROR(@"Image at %ix%i pixels is too big to fit in texture", width, height);
#endif
		width /= 2;
		height /= 2;
		transform = CGAffineTransformScale(transform, 0.5, 0.5);
		imageSize.width *= 0.5;
		imageSize.height *= 0.5;
	}
	
	switch(pixelFormat) {
		
		case kAC3DTexturePixelFormat_RGBA8888:
		case kAC3DTexturePixelFormat_RGBA4444:
		colorSpace = CGColorSpaceCreateDeviceRGB();
		data = malloc(height * width * 4);
		context = CGBitmapContextCreate(data, width, height, 8, 4 * width, colorSpace, kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);
		CGColorSpaceRelease(colorSpace);
		break;
		
		case kAC3DTexturePixelFormat_RGBA5551:
		colorSpace = CGColorSpaceCreateDeviceRGB();
		data = malloc(height * width * 2);
		context = CGBitmapContextCreate(data, width, height, 5, 2 * width, colorSpace, kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder16Little);
		CGColorSpaceRelease(colorSpace);
		break;
		
		case kAC3DTexturePixelFormat_RGB888:
		case kAC3DTexturePixelFormat_RGB565:
		colorSpace = CGColorSpaceCreateDeviceRGB();
		data = malloc(height * width * 4);
		context = CGBitmapContextCreate(data, width, height, 8, 4 * width, colorSpace, kCGImageAlphaNoneSkipLast | kCGBitmapByteOrder32Big);
		CGColorSpaceRelease(colorSpace);
		break;
		
		case kAC3DTexturePixelFormat_L8:
		colorSpace = CGColorSpaceCreateDeviceGray();
		data = malloc(height * width);
		context = CGBitmapContextCreate(data, width, height, 8, width, colorSpace, kCGImageAlphaNone);
		CGColorSpaceRelease(colorSpace);
		break;
		
		case kAC3DTexturePixelFormat_A8:
		data = malloc(height * width);
		context = CGBitmapContextCreate(data, width, height, 8, width, NULL, kCGImageAlphaOnly);
		break;
		
		case kAC3DTexturePixelFormat_LA88:
		colorSpace = CGColorSpaceCreateDeviceRGB();
		data = malloc(height * width * 4);
		context = CGBitmapContextCreate(data, width, height, 8, 4 * width, colorSpace, kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);
		CGColorSpaceRelease(colorSpace);
		break;
		
		default:
		[NSException raise:NSInternalInconsistencyException format:@"Invalid pixel format"];
		
	}
	if(context == NULL) {
		REPORT_ERROR(@"Failed creating CGBitmapContext", NULL);
		free(data);
		[self release];
		return nil;
	}
	
	if(sizeToFit)
	CGContextScaleCTM(context, (CGFloat)width / imageSize.width, (CGFloat)height / imageSize.height);
	else {
		CGContextClearRect(context, CGRectMake(0, 0, width, height));
		CGContextTranslateCTM(context, 0, height - imageSize.height);
	}
	if(!CGAffineTransformIsIdentity(transform))
	CGContextConcatCTM(context, transform);
	CGContextDrawImage(context, CGRectMake(0, 0, CGImageGetWidth(image), CGImageGetHeight(image)), image);
	
	//Convert "-RRRRRGGGGGBBBBB" to "RRRRRGGGGGBBBBBA"
	if(pixelFormat == kAC3DTexturePixelFormat_RGBA5551) {
		outPixel16 = (unsigned short*)data;
		for(i = 0; i < width * height; ++i, ++outPixel16)
		*outPixel16 = *outPixel16 << 1 | 0x0001;
#if __DEBUG__
		REPORT_ERROR(@"Falling off fast-path converting pixel data from ARGB1555 to RGBA5551", NULL);
#endif
	}
	//Convert "RRRRRRRRRGGGGGGGGBBBBBBBBAAAAAAAA" to "RRRRRRRRRGGGGGGGGBBBBBBBB"
	else if(pixelFormat == kAC3DTexturePixelFormat_RGB888) {
		tempData = malloc(height * width * 3);
		inPixel8 = (unsigned char*)data;
		outPixel8 = (unsigned char*)tempData;
		for(i = 0; i < width * height; ++i) {
			*outPixel8++ = *inPixel8++;
			*outPixel8++ = *inPixel8++;
			*outPixel8++ = *inPixel8++;
			inPixel8++;
		}
		free(data);
		data = tempData;
#if __DEBUG__
		REPORT_ERROR(@"Falling off fast-path converting pixel data from RGBA8888 to RGB888", NULL);
#endif
	}
	//Convert "RRRRRRRRRGGGGGGGGBBBBBBBBAAAAAAAA" to "RRRRRGGGGGGBBBBB"
	else if(pixelFormat == kAC3DTexturePixelFormat_RGB565) {
		tempData = malloc(height * width * 2);
		inPixel32 = (unsigned int*)data;
		outPixel16 = (unsigned short*)tempData;
		for(i = 0; i < width * height; ++i, ++inPixel32)
		*outPixel16++ = ((((*inPixel32 >> 0) & 0xFF) >> 3) << 11) | ((((*inPixel32 >> 8) & 0xFF) >> 2) << 5) | ((((*inPixel32 >> 16) & 0xFF) >> 3) << 0);
		free(data);
		data = tempData;
#if __DEBUG__
		REPORT_ERROR(@"Falling off fast-path converting pixel data from RGBA8888 to RGB565", NULL);
#endif
	}
	//Convert "RRRRRRRRRGGGGGGGGBBBBBBBBAAAAAAAA" to "RRRRRGGGGBBBBAAAA"
	else if(pixelFormat == kAC3DTexturePixelFormat_RGBA4444) {
		tempData = malloc(height * width * 2);
		inPixel32 = (unsigned int*)data;
		outPixel16 = (unsigned short*)tempData;
		for(i = 0; i < width * height; ++i, ++inPixel32)
		*outPixel16++ = ((((*inPixel32 >> 0) & 0xFF) >> 4) << 12) | ((((*inPixel32 >> 8) & 0xFF) >> 4) << 8) | ((((*inPixel32 >> 16) & 0xFF) >> 4) << 4) | ((((*inPixel32 >> 24) & 0xFF) >> 4) << 0);
		free(data);
		data = tempData;
#if __DEBUG__
		REPORT_ERROR(@"Falling off fast-path converting pixel data from RGBA8888 to RGBA4444", NULL);
#endif
	}
	//Convert "RRRRRRRRRGGGGGGGGBBBBBBBBAAAAAAAA" to "LLLLLLLLAAAAAAAA"
	else if(pixelFormat == kAC3DTexturePixelFormat_LA88) {
		tempData = malloc(height * width * 3);
		inPixel8 = (unsigned char*)data;
		outPixel8 = (unsigned char*)tempData;
		for(i = 0; i < width * height; ++i) {
			*outPixel8++ = *inPixel8++;
			inPixel8 += 2;
			*outPixel8++ = *inPixel8++;
		}
		free(data);
		data = tempData;
#if __DEBUG__
		REPORT_ERROR(@"Falling off fast-path converting pixel data from RGBA8888 to LA88", NULL);
#endif
	}
	
	self = [self initWithData:data pixelFormat:pixelFormat pixelsWide:width pixelsHigh:height contentSize:imageSize];
	
	CGContextRelease(context);
	free(data);
	
	return self;
}

@end

@implementation AC3DTexture (Text)

- (id) initWithString:(NSString*)string dimensions:(CGSize)dimensions alignment:(UITextAlignment)alignment fontName:(NSString*)name fontSize:(CGFloat)size
{
	return [self initWithString:string dimensions:dimensions alignment:alignment font:[UIFont fontWithName:name size:size]];
}

- (id) initWithString:(NSString*)string dimensions:(CGSize)dimensions alignment:(UITextAlignment)alignment font:(UIFont*)font
{
	NSUInteger				width,
							height,
							i;
	CGContextRef			context;
	void*					data;
	CGColorSpaceRef			colorSpace;
	
	if(font == nil) {
		REPORT_ERROR(@"Invalid font", NULL);
		[self release];
		return nil;
	}
	
	width = dimensions.width;
	if((width != 1) && (width & (width - 1))) {
		i = 1;
		while(i < width)
		i *= 2;
		width = i;
	}
	height = dimensions.height;
	if((height != 1) && (height & (height - 1))) {
		i = 1;
		while(i < height)
		i *= 2;
		height = i;
	}
	
	colorSpace = CGColorSpaceCreateDeviceGray();
	data = calloc(height, width);
	context = CGBitmapContextCreate(data, width, height, 8, width, colorSpace, kCGImageAlphaNone);
	CGColorSpaceRelease(colorSpace);
	if(context == NULL) {
		REPORT_ERROR(@"Failed creating CGBitmapContext", NULL);
		free(data);
		[self release];
		return nil;
	}
	
	CGContextSetGrayFillColor(context, 1.0, 1.0);
	CGContextTranslateCTM(context, 0.0, height);
	CGContextScaleCTM(context, 1.0, -1.0); //NOTE: NSString draws in UIKit referential i.e. renders upside-down compared to CGBitmapContext referential
	UIGraphicsPushContext(context);
		[string drawInRect:CGRectMake(0, 0, dimensions.width, dimensions.height) withFont:font lineBreakMode:UILineBreakModeWordWrap alignment:alignment];
	UIGraphicsPopContext();
	
	self = [self initWithData:data pixelFormat:kAC3DTexturePixelFormat_L8 pixelsWide:width pixelsHigh:height contentSize:dimensions];
	
	CGContextRelease(context);
	free(data);
	
	return self;
}

@end

@implementation AC3DTexture (Drawing)

- (void) preload
{
	glMatrixMode(GL_PROJECTION);
	glPushMatrix();
	glLoadIdentity();
	glMatrixMode(GL_MODELVIEW);
	glPushMatrix();
	glLoadIdentity();
	
	[self drawInRect:CGRectMake(-2, -2, 0.1, 0.1)];
	
	glPopMatrix();
	glMatrixMode(GL_PROJECTION);
	glPopMatrix();
}

- (void) drawAtPoint:(CGPoint)point
{
	[self drawAtPoint:point depth:0.0];
}

- (void) drawAtPoint:(CGPoint)point depth:(CGFloat)depth
{
	GLfloat				coordinates[] = {
							0,				_maxT,
							_maxS,			_maxT,
							0,				0,
							_maxS,			0
						};
	GLfloat				width = (GLfloat)_width * _maxS,
						height = (GLfloat)_height * _maxT;
	GLfloat				vertices[] = {
							-width / 2 + point.x,		-height / 2 + point.y,		depth,
							width / 2 + point.x,		-height / 2 + point.y,		depth,
							-width / 2 + point.x,		height / 2 + point.y,		depth,
							width / 2 + point.x,		height / 2 + point.y,		depth
						};
	
	glBindTexture(GL_TEXTURE_2D, _name);
	glVertexPointer(3, GL_FLOAT, 0, vertices);
	glTexCoordPointer(2, GL_FLOAT, 0, coordinates);
	glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
}

- (void) drawInRect:(CGRect)rect
{
	[self drawInRect:rect depth:0.0];
}

- (void) drawInRect:(CGRect)rect depth:(CGFloat)depth
{
	GLfloat				coordinates[] = {
							0,				_maxT,
							_maxS,			_maxT,
							0,				0,
							_maxS,			0
						};
	GLfloat				vertices[] = {
							rect.origin.x,							rect.origin.y,							depth,
							rect.origin.x + rect.size.width,		rect.origin.y,							depth,
							rect.origin.x,							rect.origin.y + rect.size.height,		depth,
							rect.origin.x + rect.size.width,		rect.origin.y + rect.size.height,		depth
						};
	
	glBindTexture(GL_TEXTURE_2D, _name);
	glVertexPointer(3, GL_FLOAT, 0, vertices);
	glTexCoordPointer(2, GL_FLOAT, 0, coordinates);
	glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
}

@end