/*

File: EAGLView.m

Abstract: The EAGLView class is responsible for rendering the GL view.

Version: 1.5

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*/

#import <QuartzCore/QuartzCore.h>

#import <OpenGLES/EAGLDrawable.h>

#import "EAGLView.h"

#import "PVRTexture.h"

#define USE_DEPTH_BUFFER 0

// A class extension to declare private methods

@interface EAGLView ()

@property (nonatomic, retain) EAGLContext *context;

- (BOOL)createFramebuffer;

- (void)destroyFramebuffer;

- (void)updateSettings;

@end

@implementation EAGLView

@synthesize compressionSupported = _compressionSupported;

@synthesize anisotropySupported = _anisotropySupported;

@dynamic compressionSetting;

@dynamic mipmapFilterSetting;

@dynamic filterSetting;

@synthesize context = _context;

- (void)loadImageFile:(NSString *)name ofType:(NSString *)extension mipmap:(BOOL)mipmap texture:(uint32_t)texture

{

UIImage *image;

int width, height;

CGImageRef cgImage;

GLubyte *data;

CGContextRef cgContext;

CGColorSpaceRef colorSpace;

GLenum err;

image = [UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:name ofType:extension]];

if (image == nil)

{

NSLog(@"Failed to load %@.%@", name, extension);

return;

}

cgImage = [image CGImage];

width = CGImageGetWidth(cgImage);

height = CGImageGetHeight(cgImage);

colorSpace = CGColorSpaceCreateDeviceRGB();

// Malloc may be used instead of calloc if your cg image has dimensions equal to the dimensions of the cg bitmap context

data = (GLubyte *)calloc(width * height * 4, sizeof(GLubyte));

cgContext = CGBitmapContextCreate(data, width, height, 8, width * 4, colorSpace, kCGImageAlphaPremultipliedLast);

if (cgContext != NULL)

{

// Set the blend mode to copy. We don't care about the previous contents.

CGContextSetBlendMode(cgContext, kCGBlendModeCopy);

CGContextDrawImage(cgContext, CGRectMake(0.0f, 0.0f, width, height), cgImage);

glGenTextures(1, &(_textures[texture]));

glBindTexture(GL_TEXTURE_2D, _textures[texture]);

if (mipmap)

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);

else

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, data);

if (mipmap)

glGenerateMipmapOES(GL_TEXTURE_2D);

err = glGetError();

if (err != GL_NO_ERROR)

NSLog(@"Error uploading texture. glError: 0x%04X", err);

CGContextRelease(cgContext);

}

free(data);

CGColorSpaceRelease(colorSpace);

}

- (void)loadTextures

{

if (_compressionSupported)

{

PVRTexture *pvrTexture;

NSArray *names = [NSArray arrayWithObjects:@"Brick_mipmap_4", @"Brick_mipmap_2", @"Brick_4", @"Brick_2", nil];

[EAGLContext setCurrentContext:_context];

[_pvrTextures removeAllObjects];

for (int i=0; i < [names count]; i++)

{

pvrTexture = [PVRTexture pvrTextureWithContentsOfFile:[[NSBundle mainBundle] pathForResource:[names objectAtIndex:i] ofType:@"pvr"]];

if (pvrTexture == nil)

NSLog(@"Failed to load %@.pvr", [names objectAtIndex:i]);

else

_textures[i] = [pvrTexture name];

[_pvrTextures addObject:pvrTexture];

}

}

[self loadImageFile:@"Brick" ofType:@"png" mipmap:TRUE texture:kTextureMipmap];

[self loadImageFile:@"Brick" ofType:@"png" mipmap:FALSE texture:kTexture];

}

// You must implement this method

+ (Class)layerClass

{

return [CAEAGLLayer class];

}

- (Compression)compressionSetting

{

return _compressionSetting;

}

- (MipmipFilter)mipmapFilterSetting

{

return _mipmapFilterSetting;

}

- (Filter)filterSetting

{

return _filterSetting;

}

- (void)setCompressionSetting:(Compression)setting

{

_compressionSetting = setting;

[self updateSettings];

[self drawView];

}

- (void)setMipmapFilterSetting:(MipmipFilter)setting

{

_mipmapFilterSetting = setting;

[self updateSettings];

[self drawView];

}

- (void)setFilterSetting:(Filter)setting

{

_filterSetting = setting;

[self updateSettings];

[self drawView];

}

- (void)updateSettings

{

// choose texture name

if (_mipmapFilterSetting == kMipmapFilterOff)

{

if (_compressionSetting == kCompressionFourBPP)

_texSelection = kTexturePvrtc4;

else if (_compressionSetting == kCompressionTwoBPP)

_texSelection = kTexturePvrtc2;

else if (_compressionSetting == kCompressionOff)

_texSelection = kTexture;

}

else

{

if (_compressionSetting == kCompressionFourBPP)

_texSelection = kTexturePvrtcMipmap4;

else if (_compressionSetting == kCompressionTwoBPP)

_texSelection = kTexturePvrtcMipmap2;

else if (_compressionSetting == kCompressionOff)

_texSelection = kTextureMipmap;

}

// choose filter settings

if (_mipmapFilterSetting == kMipmapFilterOff)

{

if (_filterSetting == kFilterNearest)

{

_minTexParam = GL_NEAREST;

_magTexParam = GL_NEAREST;

}

else if (_filterSetting == kFilterLinear || _filterSetting == kFilterSuper)

{

_minTexParam = GL_LINEAR;

_magTexParam = GL_LINEAR;

}

}

else if (_mipmapFilterSetting == kMipmapFilterNearest)

{

if (_filterSetting == kFilterNearest)

{

_minTexParam = GL_NEAREST_MIPMAP_NEAREST;

_magTexParam = GL_NEAREST;

}

else if (_filterSetting == kFilterLinear || _filterSetting == kFilterSuper)

{

_minTexParam = GL_LINEAR_MIPMAP_NEAREST;

_magTexParam = GL_LINEAR;

}

}

else if (_mipmapFilterSetting == kMipmapFilterLinear)

{

if (_filterSetting == kFilterNearest)

{

_minTexParam = GL_NEAREST_MIPMAP_LINEAR;

_magTexParam = GL_NEAREST;

}

else if (_filterSetting == kFilterLinear || _filterSetting == kFilterSuper)

{

_minTexParam = GL_LINEAR_MIPMAP_LINEAR;

_magTexParam = GL_LINEAR;

}

}

if (_filterSetting == kFilterSuper)

_anisotropyTexParam = 2.0f;

else

_anisotropyTexParam = 1.0f;

}

- (BOOL)extensionSupported:(NSString *)name

{

NSString *extensionsString = [NSString stringWithCString:(char *)glGetString(GL_EXTENSIONS) encoding:NSUTF8StringEncoding];

NSArray *extensionsNames = [extensionsString componentsSeparatedByString:@" "];

return [extensionsNames containsObject:name];

}

// The GL view is stored in the nib file. When it's unarchived it's sent -initWithCoder:

- (id)initWithCoder:(NSCoder*)coder

{

if ((self = [super initWithCoder:coder]))

{

// Get the layer

CAEAGLLayer *eaglLayer = (CAEAGLLayer *)self.layer;

eaglLayer.opaque = YES;

eaglLayer.drawableProperties = [NSDictionary dictionaryWithObjectsAndKeys:

[NSNumber numberWithBool:NO], kEAGLDrawablePropertyRetainedBacking, kEAGLColorFormatRGBA8, kEAGLDrawablePropertyColorFormat, nil];

_context = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES1];

if (!_context || ![EAGLContext setCurrentContext:_context])

{

[self release];

return nil;

}

_scale = 1.5f;

_rotate = 0.0f;

_compressionSetting = kCompressionOff;

_mipmapFilterSetting = kMipmapFilterOff;

_filterSetting = kFilterNearest;

_texSelection = kTexture;

_minTexParam = GL_NEAREST;

_magTexParam = GL_NEAREST;

_anisotropyTexParam = 1.0f;

// PVRTC textures will not be loaded if the PVRTC extension is not supported.

// UI selection for compression levels will also be disabled.

_compressionSupported = [self extensionSupported:@"GL_IMG_texture_compression_pvrtc"];

// The use of GL_TEXTURE_MAX_ANISOTROPY_EXT will be avoided if anisotropic filtering is not supported.

// UI selection for anisotropic filtering will also be disabled.

_anisotropySupported = [self extensionSupported:@"GL_EXT_texture_filter_anisotropic"];

_pvrTextures = [[NSMutableArray alloc] initWithCapacity:10];

[self loadTextures];

[self setMultipleTouchEnabled:YES];

}

return self;

}

- (void)drawView

{

const GLfloat squareVertices[] = {

-1.0f, -1.0f,

1.0f, -1.0f,

-1.0f, 1.0f,

1.0f, 1.0f

};

const GLfloat squareTexCoords[] = {

0.0, 1.0,

1.0, 1.0,

0.0, 0.0,

1.0, 0.0

};

GLenum err;

[EAGLContext setCurrentContext:_context];

glBindFramebufferOES(GL_FRAMEBUFFER_OES, _viewFramebuffer);

glViewport(0, 0, _backingWidth, _backingHeight);

glMatrixMode(GL_PROJECTION);

glLoadIdentity();

glFrustumf(-1.0f, 1.0f, -1.5, 1.5, 1.0f, 10.0f);

glMatrixMode(GL_MODELVIEW);

glLoadIdentity();

glScalef(_scale, _scale, 1.0f);

glTranslatef(0.0f, 0.0f, -2.0f);

glRotatef(_rotate, 1.0f, 0.0f, 0.0f);

glClearColor(0.5f, 0.5f, 0.5f, 1.0f);

glClear(GL_COLOR_BUFFER_BIT);

glVertexPointer(2, GL_FLOAT, 0, squareVertices);

glEnableClientState(GL_VERTEX_ARRAY);

glTexCoordPointer(2, GL_FLOAT, 0, squareTexCoords);

glEnableClientState(GL_TEXTURE_COORD_ARRAY);

glEnable(GL_TEXTURE_2D);

glBindTexture(GL_TEXTURE_2D, _textures[_texSelection]);

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, _minTexParam);

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, _magTexParam);

if (_anisotropySupported)

glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAX_ANISOTROPY_EXT, _anisotropyTexParam);

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);

glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);

glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);

glDisable(GL_TEXTURE_2D);

glBindRenderbufferOES(GL_RENDERBUFFER_OES, _viewRenderbuffer);

[_context presentRenderbuffer:GL_RENDERBUFFER_OES];

err = glGetError();

if (err != GL_NO_ERROR)

NSLog(@"Error in frame. glError: 0x%04X", err);

}

- (void)layoutSubviews

{

[EAGLContext setCurrentContext:_context];

[self destroyFramebuffer];

[self createFramebuffer];

[self drawView];

}

- (BOOL)createFramebuffer

{

glGenFramebuffersOES(1, &_viewFramebuffer);

glGenRenderbuffersOES(1, &_viewRenderbuffer);

glBindFramebufferOES(GL_FRAMEBUFFER_OES, _viewFramebuffer);

glBindRenderbufferOES(GL_RENDERBUFFER_OES, _viewRenderbuffer);

[_context renderbufferStorage:GL_RENDERBUFFER_OES fromDrawable:(CAEAGLLayer*)self.layer];

glFramebufferRenderbufferOES(GL_FRAMEBUFFER_OES, GL_COLOR_ATTACHMENT0_OES, GL_RENDERBUFFER_OES, _viewRenderbuffer);

glGetRenderbufferParameterivOES(GL_RENDERBUFFER_OES, GL_RENDERBUFFER_WIDTH_OES, &_backingWidth);

glGetRenderbufferParameterivOES(GL_RENDERBUFFER_OES, GL_RENDERBUFFER_HEIGHT_OES, &_backingHeight);

if (USE_DEPTH_BUFFER)

{

glGenRenderbuffersOES(1, &_depthRenderbuffer);

glBindRenderbufferOES(GL_RENDERBUFFER_OES, _depthRenderbuffer);

glRenderbufferStorageOES(GL_RENDERBUFFER_OES, GL_DEPTH_COMPONENT16_OES, _backingWidth, _backingHeight);

glFramebufferRenderbufferOES(GL_FRAMEBUFFER_OES, GL_DEPTH_ATTACHMENT_OES, GL_RENDERBUFFER_OES, _depthRenderbuffer);

}

if(glCheckFramebufferStatusOES(GL_FRAMEBUFFER_OES) != GL_FRAMEBUFFER_COMPLETE_OES)

{

NSLog(@"failed to make complete framebuffer object %x", glCheckFramebufferStatusOES(GL_FRAMEBUFFER_OES));

return NO;

}

return YES;

}

- (void)destroyFramebuffer

{

glDeleteFramebuffersOES(1, &_viewFramebuffer);

_viewFramebuffer = 0;

glDeleteRenderbuffersOES(1, &_viewRenderbuffer);

_viewRenderbuffer = 0;

if(_depthRenderbuffer)

{

glDeleteRenderbuffersOES(1, &_depthRenderbuffer);

_depthRenderbuffer = 0;

}

}

- (void)dealloc

{

if ([EAGLContext currentContext] == _context)

[EAGLContext setCurrentContext:nil];

if (_textures[kTexture] != 0)

glDeleteTextures(1, &_textures[kTexture]);

if (_textures[kTextureMipmap] != 0)

glDeleteTextures(1, &_textures[kTextureMipmap]);

[_pvrTextures release];

[_context release];

[super dealloc];

}

- (float)distanceFromPoint:(CGPoint)pointA toPoint:(CGPoint)pointB

{

float xD = fabs(pointA.x - pointB.x);

float yD = fabs(pointA.y - pointB.y);

return sqrt(xD*xD + yD*yD);

}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event

{

UITouch *touchA, *touchB;

CGPoint pointA, pointB;

if ([touches count] == 1)

{

touchA = [[touches allObjects] objectAtIndex:0];

pointA = [touchA locationInView:self];

pointB = [touchA previousLocationInView:self];

float yDistance = pointA.y - pointB.y;

_rotate += 0.5 * yDistance;

[self drawView];

}

else if ([touches count] == 2)

{

touchA = [[touches allObjects] objectAtIndex:0];

touchB = [[touches allObjects] objectAtIndex:1];

pointA = [touchA locationInView:self];

pointB = [touchB locationInView:self];

float currDistance = [self distanceFromPoint:pointA toPoint:pointB];

pointA = [touchA previousLocationInView:self];

pointB = [touchB previousLocationInView:self];

float prevDistance = [self distanceFromPoint:pointA toPoint:pointB];

_scale += 0.005 * (currDistance - prevDistance);

if (_scale > 10.0f)

_scale = 10.0f;

else if (_scale < 0.025f)

_scale = 0.025f;

[self drawView];

}

}

@end