Use Core Graphics draw triangle

gistfile1.c

void drawTriangle(CGContextRef context, CGPoint startPoint, CGPoint secondPoint, CGPoint lastPoint)
{
    CGContextSaveGState(context);
    CGContextMoveToPoint(context, startPoint.x, startPoint.y);
    CGContextAddLineToPoint(context, secondPoint.x, secondPoint.y);
    CGContextAddLineToPoint(context, lastPoint.x, lastPoint.y);
    CGContextClosePath(context);
    CGContextFillPath(context);
    CGContextRestoreGState(context);
}