convert NSMutableArray to CGPoint Array - ios

Question

the typical answer will be "you can convert it to nsvalue and then use [element CGPointValue];
but in my case i need to generate array of type CGPoint , as i need it in a built in function below :
static CGPathRef createClosedPathWithPoints(const CGPoint *points, size_t count) {
CGMutablePathRef path = CGPathCreateMutable();
CGPathAddLines(path, NULL, points, count);
CGPathCloseSubpath(path);
return path;
}
so , i need to pass the exact datatype , as i can't parse it element by element , or i need a way to everytime the user make a specific action , i add it's CGPoint to array of CGPoints :((
thanks in advance
edit :
i have tried malloc and making c array but the result of the function was not desirable , i tested and made infinity for loop to that malloc array , and it's too large not just like the size i sat , and contain garbage so the result went wrong
this is the mutable array
pointToPoints = [NSMutableArray new];
[pointToPoints addObject:[NSValue valueWithCGPoint:tempPoint] ];

Answer 1

Here is something that will create a closed path from an NSArray of NSValue created with CGPoint using the code your provided:
BOOL isCGPoint(NSValue *value){
return value && strcmp([value objCType], #encode(CGPoint)) == 0;
}
- (CGPathRef) closedPathFromPointArray:(NSArray *)points{
CGMutablePathRef path = CGPathCreateMutable();
if(points.count){
CGPoint origin = ((NSValue *)points[0]).CGPointValue;
CGPathMoveToPoint (path, NULL, origin.x, origin.y);
// see https://developer.apple.com/library/mac/documentation/GraphicsImaging/Reference/CGPath/#//apple_ref/c/func/CGPathAddLines
for(NSValue *value in points){
CGPathAddLineToPoint (path, NULL, value.CGPointValue.x, value.CGPointValue.y);
}
}
CGPathCloseSubpath(path);
return path;
}
As you see, you don't really need malloc, or even creating a C array of CGPoint. This assumes you only need this array for creating the closed path.
Two extra things of note:
See the commented link for CGPathAddLines, as it describes how CGPathAddLines works internally. This gives you the hint about how to go about this.
The isCGPoint function is included so you can test if a given NSValue instance was actually created using [NSValue valueWithCGPoint:]. My previous answer checked this, but I thought it was ooverkill to check everywhere. In any case, it's included here for didactic purposes.

Answer 2

CGPoint *points = malloc(sizeof(CGPoint) * mutableArrayOfPoints.count);
for (int i = 0; i < mutableArrayOfPoints.count; i++) {
points[i] = [mutableArrayOfPoints[i] pointValue];
}
The above is from memory. I haven't used malloc() in ages, so you may need to adjust syntax.