OpenGL draw base functions

-(void) draw
{
CGSize s = [[CCDirector sharedDirector] winSize];

// draw a simple line
// The default state is:
// Line Width: 1
// color: 255,255,255,255 (white, non-transparent)
// Anti-Aliased
glEnable(GL_LINE_SMOOTH);

 
ccDrawLine( ccp(0, 0), ccp(s.width, s.height) );

// line: color, width, aliased
// glLineWidth > 1 and GL_LINE_SMOOTH are not compatible
// GL_SMOOTH_LINE_WIDTH_RANGE = (1,1) on iPhone
glDisable(GL_LINE_SMOOTH);
glLineWidth( 5.0f );
glColor4ub(255,0,0,255);
ccDrawLine( ccp(0, s.height), ccp(s.width, 0) );

// TIP:
// If you are going to use always the same color or width, you don't
// need to call it before every draw
//
// Remember: OpenGL is a state-machine.

// draw big point in the center
glPointSize(64);
glColor4ub(0,0,255,128);
ccDrawPoint( ccp(s.width / 2, s.height / 2) );

// draw 4 small points
CGPoint points[] = { ccp(60,60), ccp(70,70), ccp(60,70), ccp(70,60) };
glPointSize(4);
glColor4ub(0,255,255,255);
ccDrawPoints( points, 4);

// draw a green circle with 10 segments
glLineWidth(16);
glColor4ub(0, 255, 0, 255);
ccDrawCircle( ccp(s.width/2, s.height/2), 100, 0, 10, NO);

// draw a green circle with 50 segments with line to center
glLineWidth(2);
glColor4ub(0, 255, 255, 255);
ccDrawCircle( ccp(s.width/2, s.height/2), 50, CC_DEGREES_TO_RADIANS(90), 50, YES);

// open yellow poly
glColor4ub(255, 255, 0, 255);
glLineWidth(10);
CGPoint vertices[] = { ccp(0,0), ccp(50,50), ccp(100,50), ccp(100,100), ccp(50,100) };
ccDrawPoly( vertices, 5, NO);

// closed purble poly
glColor4ub(255, 0, 255, 255);
glLineWidth(2);
CGPoint vertices2[] = { ccp(30,130), ccp(30,230), ccp(50,200) };
ccDrawPoly( vertices2, 3, YES);

// closed purble poly 正方形
    glColor4ub(255, 0, 255, 255);
    glLineWidth(2);
    CGPoint vertices3[] = { ccp(30,130), ccp(30,230), ccp(60,230), ccp(60,130) };
    ccDrawPoly( vertices3, 4, YES);

// draw quad bezier path
ccDrawQuadBezier(ccp(0,s.height), ccp(s.width/2,s.height/2), ccp(s.width,s.height), 50);

// draw cubic bezier path
ccDrawCubicBezier(ccp(s.width/2, s.height/2), ccp(s.width/2+30,s.height/2+50), ccp(s.width/2+60,s.height/2-50),ccp(s.width, s.height/2),100);

// restore original values
glLineWidth(1);
glColor4ub(255,255,255,255);
glPointSize(1);
}

蜘蛛例子

// Only draw this debugging information in, well, debug builds.
-(void) draw
{
#if DEBUG
    // Iterate through all nodes of the layer.
    CCNode* node;
    CCARRAY_FOREACH([self children], node)
    {
        // Make sure the node is a CCSprite and has the right tags.
        if ([node isKindOfClass:[CCSprite class]] && (node.tag == 1 || node.tag == 2))
        {
            // The sprite's collision radius is a percentage of its image width. Use that to draw a circle
            // which represents the sprite's collision radius.
            CCSprite* sprite = (CCSprite*)node;
            float radius = [sprite texture].contentSize.width * 0.4f;
            float angle = 0;
            int numSegments = 10;
            bool drawLineToCenter = NO;
            ccDrawCircle(sprite.position, radius, angle, numSegments, drawLineToCenter);
        }
    }
#endif

    CGSize screenSize = [[CCDirector sharedDirector] winSize];
    
    // always keep variables you have to calculate only once outside the loop
    float threadCutPosition = screenSize.height * 0.75f;

    // Draw a spider thread using OpenGL
    // CCARRAY_FOREACH is a bit faster than regular for loop
    CCSprite* spider;
    CCARRAY_FOREACH(spiders, spider)
    {
        // only draw thread up to a certain point
        if (spider.position.y > threadCutPosition)
        {
            // vary thread position a little so it looks a bit more dynamic
            float threadX = spider.position.x + (CCRANDOM_0_1() * 2.0f - 1.0f);
            
            glColor4f(0.5f, 0.5f, 0.5f, 1.0f);
            ccDrawLine(spider.position, CGPointMake(threadX, screenSize.height));
        }
    }
}

@end