I am working on an app for iPhone and iPod Touch that has to show complex mathematical equations like algebraic, integration, summation formulas along with some text.
For that I have used Quartz2D and below is what I have created. Can anyone please verify if this is the correct procedure to draw an equation?
I have to show lots of text with inline equations (and that too dynamic) - I am sure using this procedure will be a task to make that thing dynamic.
- (void)drawRect:(CGRect)rect
{
float xaxis = 3.0f;
NSString *textString = @"L";
[textString drawAtPoint:CGPointMake(xaxis, 50.) withFont:[UIFont fontWithName:@"Helvetica-Oblique" size:20]];
xaxis += 12.0f;
textString = @"(";
[textString drawAtPoint:CGPointMake(xaxis, 30.) withFont:[UIFont fontWithName:@"Helvetica" size:50]];
textString = @"N";
xaxis += 12.0f;
[textString drawAtPoint:CGPointMake(xaxis, 50.) withFont:[UIFont fontWithName:@"Helvetica-Oblique" size:20]];
unichar oneChar[] = {0x2206};
xaxis += 31.0f;
textString = getTextString(oneChar, 1);
[textString drawAtPoint:CGPointMake(xaxis, 37.) withFont:[UIFont fontWithName:@"Helvetica" size:22]];
unichar twoChar[] = {0x03C9};
xaxis += 15.0f;
textString = getTextString(twoChar, 1);
[textString drawAtPoint:CGPointMake(xaxis, 38.) withFont:[UIFont fontWithName:@"Helvetica" size:20]];
xaxis += 15.0f;
textString = @"k";
[textString drawAtPoint:CGPointMake(xaxis, 48.) withFont:[UIFont fontWithName:@"Helvetica" size:12]];
CGContextRef myContext = UIGraphicsGetCurrentContext();
CGContextSetLineWidth(myContext, 2);
CGContextSetStrokeColorWithColor(myContext, [UIColor blackColor].CGColor);
CGContextMoveToPoint(myContext, 45, 65);
CGContextAddLineToPoint(myContext, 110, 65);
CGContextStrokePath(myContext);
xaxis -= 40.0f;
unichar threeChar[] = {0x03C9};
textString = getTextString(threeChar, 1);
[textString drawAtPoint:CGPointMake(xaxis, 64.) withFont:[UIFont fontWithName:@"Helvetica" size:20]];
xaxis += 15.0f;
textString = @"res";
[textString drawAtPoint:CGPointMake(xaxis, 74.) withFont:[UIFont fontWithName:@"Helvetica" size:12]];
xaxis += 18.0f;
unichar fourChar[] = {0x0028};
textString = getTextString(fourChar, 1);
[textString drawAtPoint:CGPointMake(xaxis, 64.) withFont:[UIFont fontWithName:@"Helvetica" size:20]];
xaxis += 5.0f;
unichar fiveChar[] = {0x03B8};
textString = getTextString(fiveChar, 1);
[textString drawAtPoint:CGPointMake(xaxis, 64.) withFont:[UIFont fontWithName:@"Helvetica-Oblique" size:20]];
xaxis += 15.0f;
textString = @")";
[textString drawAtPoint:CGPointMake(xaxis, 64.) withFont:[UIFont fontWithName:@"Helvetica" size:20]];
xaxis += 8.0f;
textString = @")";
[textString drawAtPoint:CGPointMake(xaxis, 30.) withFont:[UIFont fontWithName:@"Helvetica" size:50]];
xaxis += 15.0f;
unichar sixChar[] = {0x003D};
textString = getTextString(sixChar, 1);
[textString drawAtPoint:CGPointMake(xaxis, 50.) withFont:[UIFont fontWithName:@"Helvetica" size:20]];
xaxis += 15.0f;
textString = @"sin";
[textString drawAtPoint:CGPointMake(xaxis, 42.) withFont:[UIFont fontWithName:@"Helvetica" size:17]];
xaxis += 20.0f;
textString = @"2";
[textString drawAtPoint:CGPointMake(xaxis, 38.) withFont:[UIFont fontWithName:@"Helvetica" size:12]];
xaxis += 10.0f;
textString = @"(";
[textString drawAtPoint:CGPointMake(xaxis, 37.) withFont:[UIFont fontWithName:@"Helvetica" size:22]];
xaxis += 8.0f;
textString = @"N";
[textString drawAtPoint:CGPointMake(xaxis, 38.) withFont:[UIFont fontWithName:@"Helvetica-Oblique" size:20]];
xaxis += 18.0f;
unichar sevenChar[] = {0x03C0};
textString = getTextString(sevenChar, 1);
[textString drawAtPoint:CGPointMake(xaxis, 40.) withFont:[UIFont fontWithName:@"Helvetica" size:17]];
xaxis += 12.0f;
unichar eightChar[] = {0x2206};
textString = getTextString(eightChar, 1);
[textString drawAtPoint:CGPointMake(xaxis, 36.) withFont:[UIFont fontWithName:@"Helvetica" size:21]];
xaxis += 15.0f;
unichar nineChar[] = {0x03C9};
textString = getTextString(nineChar, 1);
[textString drawAtPoint:CGPointMake(xaxis, 38.) withFont:[UIFont fontWithName:@"Helvetica" size:20]];
xaxis += 15.0f;
textString = @"k";
[textString drawAtPoint:CGPointMake(xaxis, 47.) withFont:[UIFont fontWithName:@"Helvetica" size:12]];
xaxis += 8.0f;
textString = @"/";
[textString drawAtPoint:CGPointMake(xaxis, 38.) withFont:[UIFont fontWithName:@"Helvetica" size:24]];
xaxis += 8.0f;
unichar tenChar[] = {0x03C9};
textString = getTextString(tenChar, 1);
[textString drawAtPoint:CGPointMake(xaxis, 38.) withFont:[UIFont fontWithName:@"Helvetica" size:20]];
xaxis += 15.0f;
textString = @"res";
[textString drawAtPoint:CGPointMake(xaxis, 48.) withFont:[UIFont fontWithName:@"Helvetica" size:12]];
xaxis += 18.0f;
textString = @"(";
[textString drawAtPoint:CGPointMake(xaxis, 38.) withFont:[UIFont fontWithName:@"Helvetica" size:20]];
xaxis += 5.0f;
unichar elevenChar[] = {0x03B8};
textString = getTextString(elevenChar, 1);
[textString drawAtPoint:CGPointMake(xaxis, 38.) withFont:[UIFont fontWithName:@"Helvetica-Oblique" size:20]];
xaxis += 12.0f;
textString = @")";
[textString drawAtPoint:CGPointMake(xaxis, 38.) withFont:[UIFont fontWithName:@"Helvetica" size:20]];
xaxis += 6.0f;
textString = @")";
[textString drawAtPoint:CGPointMake(xaxis, 37.) withFont:[UIFont fontWithName:@"Helvetica" size:22]];
CGContextSetLineWidth(myContext, 2);
CGContextSetStrokeColorWithColor(myContext, [UIColor blackColor].CGColor);
CGContextMoveToPoint(myContext, 138, 65);
CGContextAddLineToPoint(myContext, 318, 65);
CGContextStrokePath(myContext);
xaxis -= 175.0f;
textString = @"N";
[textString drawAtPoint:CGPointMake(xaxis, 65.) withFont:[UIFont fontWithName:@"Helvetica-Oblique" size:20]];
xaxis += 18.0f;
textString = @"2";
[textString drawAtPoint:CGPointMake(xaxis, 63.) withFont:[UIFont fontWithName:@"Helvetica" size:12]];
xaxis += 8.0f;
textString = @"sin";
[textString drawAtPoint:CGPointMake(xaxis, 68.) withFont:[UIFont fontWithName:@"Helvetica" size:17]];
xaxis += 20.0f;
textString = @"2";
[textString drawAtPoint:CGPointMake(xaxis, 63.) withFont:[UIFont fontWithName:@"Helvetica" size:12]];
xaxis += 10.0f;
textString = @"(";
[textString drawAtPoint:CGPointMake(xaxis, 64.) withFont:[UIFont fontWithName:@"Helvetica" size:22]];
xaxis += 8.0f;
unichar twelveChar[] = {0x03C0};
textString = getTextString(twelveChar, 1);
[textString drawAtPoint:CGPointMake(xaxis, 68.) withFont:[UIFont fontWithName:@"Helvetica" size:17]];
xaxis += 12.0f;
unichar thirteenChar[] = {0x2206};
textString = getTextString(thirteenChar, 1);
[textString drawAtPoint:CGPointMake(xaxis, 65.) withFont:[UIFont fontWithName:@"Helvetica" size:21]];
xaxis += 15.0f;
unichar fourteenChar[] = {0x03C9};
textString = getTextString(fourteenChar, 1);
[textString drawAtPoint:CGPointMake(xaxis, 67.) withFont:[UIFont fontWithName:@"Helvetica" size:20]];
xaxis += 15.0f;
textString = @"k";
[textString drawAtPoint:CGPointMake(xaxis, 75.) withFont:[UIFont fontWithName:@"Helvetica" size:12]];
xaxis += 8.0f;
textString = @"/";
[textString drawAtPoint:CGPointMake(xaxis, 64.) withFont:[UIFont fontWithName:@"Helvetica" size:24]];
xaxis += 8.0f;
unichar fifteenChar[] = {0x03C9};
textString = getTextString(fifteenChar, 1);
[textString drawAtPoint:CGPointMake(xaxis, 67.) withFont:[UIFont fontWithName:@"Helvetica" size:20]];
xaxis += 15.0f;
textString = @"res";
[textString drawAtPoint:CGPointMake(xaxis, 75.) withFont:[UIFont fontWithName:@"Helvetica" size:12]];
xaxis += 18.0f;
textString = @"(";
[textString drawAtPoint:CGPointMake(xaxis, 66.) withFont:[UIFont fontWithName:@"Helvetica" size:20]];
xaxis += 5.0f;
unichar sixteenChar[] = {0x03B8};
textString = getTextString(sixteenChar, 1);
[textString drawAtPoint:CGPointMake(xaxis, 66.) withFont:[UIFont fontWithName:@"Helvetica-Oblique" size:20]];
xaxis += 12.0f;
textString = @")";
[textString drawAtPoint:CGPointMake(xaxis, 66.) withFont:[UIFont fontWithName:@"Helvetica" size:20]];
xaxis += 6.0f;
textString = @")";
[textString drawAtPoint:CGPointMake(xaxis, 64.) withFont:[UIFont fontWithName:@"Helvetica" size:22]];
xaxis = 6.0f;
textString = @"Above is the example of an equation drawn using";
[textString drawAtPoint:CGPointMake(xaxis, 120.) withFont:[UIFont fontWithName:@"Helvetica" size:14]];
xaxis = 6.0f;
textString = @"Quartz2D";
[textString drawAtPoint:CGPointMake(xaxis, 140.) withFont:[UIFont fontWithName:@"Helvetica" size:14]];
}
static NSString *getTextString(unichar chars[], int charLength)
{
NSString *uniString = [NSString stringWithCharacters:chars length: charLength];
return uniString;
}