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tleport88
12-11-2012, 01:00 PM
Hallo,
I am an opengl beginner.
I tried to display a 2d texture, but it is not displayed.
I use Xcode 4.3 and NSOpenGLView.
My Code:



@implementation MyOpenGLView

- (id)initWithFrame:(NSRect)frame
{
NSOpenGLPixelFormat * pf = [MyOpenGLView basicPixelFormat];

self = [super initWithFrame: frame pixelFormat: pf];
return self;
}

+ (NSOpenGLPixelFormat*) basicPixelFormat
{
NSOpenGLPixelFormatAttribute attributes [] = {
NSOpenGLPFAWindow,
NSOpenGLPFADoubleBuffer, // double buffered
NSOpenGLPFADepthSize, (NSOpenGLPixelFormatAttribute)16, // 16 bit depth buffer
(NSOpenGLPixelFormatAttribute)nil
};
return [[NSOpenGLPixelFormat alloc] initWithAttributes:attributes];
}

- (void) prepareOpenGL
{
glEnable(GL_DEPTH_TEST);

glShadeModel(GL_SMOOTH);
glEnable(GL_CULL_FACE);
glFrontFace(GL_CCW);
glPolygonOffset (1.0f, 1.0f);
glClearColor(0.0f, 0.0f, 0.0f, 0.5f);

if([self loadTextures])
NSLog(@"Load");
}

- (void)drawRect:(NSRect)dirtyRect
{
glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glBindTexture( GL_TEXTURE_2D, texture);
glPolygonMode(GL_FRONT_AND_BACK,GL_LINE);
glColor3f(1, 1, 1);
glBegin( GL_QUADS );
glTexCoord2f( 0.0f, 0.0f);
glVertex2f( -0.5f, -0.5f);
glTexCoord2f( 1.0f, 0.0f);
glVertex2f( 0.5f, -0.5f);
glTexCoord2f( 1.0f, 1.0f);
glVertex2f( 0.5f, 0.5f);
glTexCoord2f( 0.0f, 1.0f);
glVertex2f( -0.5f, 0.5f);
glEnd();

glFlush();
}

- (BOOL) loadTextures
{
NSImage *img = [NSImage imageNamed:@"NeHe.bmp"];
if(img == nil)
return FALSE;
else if(img.size.height == 0 || img.size.width == 0)
return FALSE;
NSBitmapImageRep *rep = [[NSBitmapImageRep alloc] initWithData: [img TIFFRepresentation]];
glGenTextures( 1, &texture);
glBindTexture( GL_TEXTURE_2D, texture);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, 0);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 0);
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
glTexImage2D( GL_TEXTURE_2D, 0, GL_RGB, rep.size.width,
rep.size.height, 0, GL_RGB,
GL_UNSIGNED_BYTE, rep.bitmapData);
return TRUE;
}
@end

Thank you for your help.