SDL - Simple DirectMedia Layer

Copyright (C) 1997-2011 Sam Lantinga

This library is free software; you can redistribute it and/or

modify it under the terms of the GNU Lesser General Public

License as published by the Free Software Foundation; either

version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public

License along with this library; if not, write to the Free Software

Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

Sam Lantinga

slouken@libsdl.org

*/

#import <QuartzCore/QuartzCore.h>

#import <OpenGLES/EAGLDrawable.h>

#import "SDL_uikitopenglview.h"

@interface SDL_uikitopenglview (privateMethods)

- (BOOL) createFramebuffer;

- (void) destroyFramebuffer;

@end

@implementation SDL_uikitopenglview

@synthesize context;

+ (Class)layerClass {

}

- (id)initWithFrame:(CGRect)frame \

retainBacking:(BOOL)retained \

rBits:(int)rBits \

gBits:(int)gBits \

bBits:(int)bBits \

aBits:(int)aBits \

depthBits:(int)depthBits \

NSString *colorFormat=nil;

BOOL useDepthBuffer;

if (rBits == 8 && gBits == 8 && bBits == 8) {

/* if user specifically requests rbg888 or some color format higher than 16bpp */

colorFormat = kEAGLColorFormatRGBA8;

}

else {

/* default case (faster) */

colorFormat = kEAGLColorFormatRGB565;

}

depthBufferFormat = 0;

if (depthBits == 24) {

useDepthBuffer = YES;

depthBufferFormat = GL_DEPTH_COMPONENT24_OES;

}

else if (depthBits == 0) {

useDepthBuffer = NO;

}

else {

/* default case when depth buffer is not disabled */

/*

strange, even when we use this, we seem to get a 24 bit depth buffer on iPhone.

perhaps that's the only depth format iPhone actually supports

*/

useDepthBuffer = YES;

depthBufferFormat = GL_DEPTH_COMPONENT16_OES;

}

if ((self = [super initWithFrame:frame])) {

// Get the layer

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

eaglLayer.opaque = YES;

eaglLayer.drawableProperties = [NSDictionary dictionaryWithObjectsAndKeys:

[NSNumber numberWithBool: retained], kEAGLDrawablePropertyRetainedBacking, colorFormat, kEAGLDrawablePropertyColorFormat, nil];

if (majorVersion > 1) {

context = [[EAGLContext alloc] initWithAPI: kEAGLRenderingAPIOpenGLES2];

} else {

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

}

if (!context || ![EAGLContext setCurrentContext:context]) {

[self release];

return nil;

}

/* create the buffers */

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 (useDepthBuffer) {

glGenRenderbuffersOES(1, &depthRenderbuffer);

glBindRenderbufferOES(GL_RENDERBUFFER_OES, depthRenderbuffer);

glRenderbufferStorageOES(GL_RENDERBUFFER_OES, depthBufferFormat, backingWidth, backingHeight);

glFramebufferRenderbufferOES(GL_FRAMEBUFFER_OES, GL_DEPTH_ATTACHMENT_OES, GL_RENDERBUFFER_OES, depthRenderbuffer);

}

if(glCheckFramebufferStatusOES(GL_FRAMEBUFFER_OES) != GL_FRAMEBUFFER_COMPLETE_OES) {

return NO;

}

/* end create buffers */

/* Use the main screen scale (for retina display support) */

if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)])

self.contentScaleFactor = [UIScreen mainScreen].scale;

}

return self;

}

- (void)updateFrame {

glBindFramebufferOES(GL_FRAMEBUFFER_OES, viewFramebuffer);

glBindRenderbufferOES(GL_RENDERBUFFER_OES, 0);

glFramebufferRenderbufferOES(GL_FRAMEBUFFER_OES, GL_COLOR_ATTACHMENT0_OES, GL_RENDERBUFFER_OES, 0);

glDeleteRenderbuffersOES(1, &viewRenderbuffer);

glGenRenderbuffersOES(1, &viewRenderbuffer);

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 (depthRenderbuffer != 0) {

glBindRenderbufferOES(GL_RENDERBUFFER_OES, depthRenderbuffer);

glRenderbufferStorageOES(GL_RENDERBUFFER_OES, depthBufferFormat, backingWidth, backingHeight);

}

// !!! FIXME: use the screen this is on!

/* Use the main screen scale (for retina display support) */

if ([[UIScreen mainScreen] respondsToSelector:@selector(scale)])

self.contentScaleFactor = [UIScreen mainScreen].scale;

}

}

- (void)swapBuffers {

glBindRenderbufferOES(GL_RENDERBUFFER_OES, viewRenderbuffer);

[context presentRenderbuffer:GL_RENDERBUFFER_OES];

}

- (void)layoutSubviews {

}

- (void)destroyFramebuffer {

glDeleteFramebuffersOES(1, &viewFramebuffer);

viewFramebuffer = 0;

glDeleteRenderbuffersOES(1, &viewRenderbuffer);

viewRenderbuffer = 0;

if (depthRenderbuffer) {

glDeleteRenderbuffersOES(1, &depthRenderbuffer);

depthRenderbuffer = 0;

}

}

- (void)dealloc {

[self destroyFramebuffer];

if ([EAGLContext currentContext] == context) {

[EAGLContext setCurrentContext:nil];

}

[context release];

[super dealloc];

}

/* vi: set ts=4 sw=4 expandtab: */