IS it possible to add an points on line in MPMovieplayercontroller..
If yes then how..Becoz as it is possible to draw the line on view .then MPMovieplayerconteoler is also an view only..
- (void)drawSquiggle:(Squiggle *)squiggle inContext:(CGContextRef)context
{
// set the drawing color to the squiggle's color
UIColor *squiggleColor = squiggle.strokeColor; // get squiggle's color
CGColorRef colorRef = [squiggleColor CGColor]; // get the CGColor
CGContextSetStrokeColorWithColor(context, colorRef);
// set the line width to the squiggle's line width
CGContextSetLineWidth(context, squiggle.lineWidth);
NSMutableArray *points = [squiggle points]; // get points from squiggle
// retrieve the NSValue object and store the value in firstPoint
CGPoint firstPoint; // declare a CGPoint
[[points objectAtIndex:0] getValue:&firstPoint];
// move to the point
CGContextMoveToPoint(context, firstPoint.x, firstPoint.y);
// draw a line from each point to the next in order
for (int i = 1; i < [points count]; i++)
{
NSValue *value = [points objectAtIndex:i]; // get the next value
CGPoint point; // declare a new point
[value getValue:&point]; // store the value in point
// draw a line to the new point
CGContextAddLineToPoint(context, point.x, point.y);
} // end for
CGContextStrokePath(context);
} // end method drawSquiggle:inContext:
end method touchesBegan:withEvent:
This is the code which i had used..
mpPlayer is the mpvideoplayer object
but it is not able to draw point on mpvideoplayer..
Is there any way out.Please help me..
There is an example in the IOS SDK that has an overlay view over a playing movie. That should be a good start.
https://developer.apple.com/library/ios/#samplecode/MoviePlayer_iPhone/Introduction/Intro.html
Related
A very simple XCode iPhone app. Blank screen, draw lines, each line is to have a unique colour given via a random number gen. I have the code to give me random colours, but I cannot get the lines to retain the colour individually. Any time the screen is drawn, the colour changes for all lines in my array.
here is the code to set the color to each line:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
for (UITouch *t in touches) {
// Is this a double-tap?
if ([t tapCount] > 1) {
[self clearAll];
return;
}
CGFloat hue = ( arc4random() % 256 / 256.0 ); // 0.0 to 1.0
CGFloat saturation = ( arc4random() % 128 / 256.0 ) + 0.5; // 0.5 to 1.0, away from white
CGFloat brightness = ( arc4random() % 128 / 256.0 ) + 0.5; // 0.5 to 1.0, away from black
Colour=[UIColor colorWithHue:hue saturation:saturation brightness:brightness alpha:1];
// Use the touch object (packed in an NSValue) as the key
NSValue *key = [NSValue valueWithPointer:t];
// Create a line for the value
CGPoint loc = [t locationInView:self];
Line *newLine = [[Line alloc] init];
[newLine setBegin:loc];
[newLine setEnd:loc];
[newLine setCOLOUR:Colour];
// Put pair in dictionary
[linesInProcess setObject:newLine forKey:key];
[newLine release];
}
}
here is the code I've been using to draw lines.
- (void)drawRect:(CGRect)rect {
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetLineWidth(context, 10.0);
CGContextSetLineCap(context, kCGLineCapRound);
for (Line *line in completeLines) {
[Colour set];
CGContextMoveToPoint(context, [line begin].x, [line begin].y);
CGContextAddLineToPoint(context, [line end].x, [line end].y);
CGContextStrokePath(context);
}
// Draw lines in process in red
[[UIColor redColor] set];
for (NSValue *v in linesInProcess) {
Line *line = [linesInProcess objectForKey:v];
CGContextMoveToPoint(context, [line begin].x, [line begin].y);
CGContextAddLineToPoint(context, [line end].x, [line end].y);
CGContextStrokePath(context);
}
}
To reiterate: I'm trying to give each line drawn on the interface a unique colour. Said colour is given by the random num gen.
Appreciate the help, people. :D
In your drawRect in the loop through linesInProcess you are not setting the color. You need to use the color information in your line object and reset the color in each loop iteration:
CGContextSetStrokeColorWithColor(context, line.COLOUR.CGColor);
or, alternatively
[line.COLOUR set];
The same applies to your completeLines loop.
PS: You would do yourself a favor by using the usual camel case variable names for your classes' properties.
I currently have the following code to try and allow the user to draw a dotted path and make a custom shape. Once they have made this shape, I wanted it to automatically be filled with colour. That isn't happening.
At the moment I am getting this error for the code below:
<Error>: CGContextClosePath: no current point.
Here's the code I'm using:
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = [touches anyObject];
CGPoint previous = [touch previousLocationInView:self];
CGPoint current = [touch locationInView:self];
#define SQR(x) ((x)*(x))
//Check for a minimal distance to avoid silly data
if ((SQR(current.x - self.previousPoint2.x) + SQR(current.y - self.previousPoint2.y)) > SQR(10))
{
float dashPhase = 5.0;
float dashLengths[] = {10, 10};
CGContextSetLineDash(context,
dashPhase, dashLengths, 2);
CGContextSetFillColorWithColor(context, [[UIColor lightGrayColor] CGColor]);
CGContextFillPath(context);
CGContextSetLineWidth(context, 2);
CGFloat gray[4] = {0.5f, 0.5f, 0.5f, 1.0f};
CGContextSetStrokeColor(context, gray);
self.brushSize = 5;
self.brushColor = [UIColor lightGrayColor];
self.previousPoint2 = self.previousPoint1;
self.previousPoint1 = previous;
self.currentPoint = current;
// calculate mid point
self.mid1 = [self pointBetween:self.previousPoint1 andPoint:self.previousPoint2];
self.mid2 = [self pointBetween:self.currentPoint andPoint:self.previousPoint1];
if(self.paths.count == 0)
{
UIBezierPath* newPath = [UIBezierPath bezierPath];
CGContextBeginPath(context);
[newPath moveToPoint:self.mid1];
[newPath addLineToPoint:self.mid2];
[self.paths addObject:newPath];
CGContextClosePath(context);
}
else
{
UIBezierPath* lastPath = [self.paths lastObject];
CGContextBeginPath(context);
[lastPath addLineToPoint:self.mid2];
[self.paths replaceObjectAtIndex:[self.paths indexOfObject:[self.paths lastObject]] withObject:lastPath];
CGContextClosePath(context);
}
//Save
[self.pathColors addObject:self.brushColor];
self.needsToRedraw = YES;
[self setNeedsDisplayInRect:[self dirtyRect]];
//[self setNeedsDisplay];
}
}
Why is this happening and why is the inside of the path not being filled with colour?
Your code has a few issues:
You should be doing your drawing in your view's drawRect: method, not the touch handler.
You never set the variable context with a value for the current context. Do that with the UIGraphicsGetCurrentContext() method. Again, within your drawRect: method.
You go through the trouble of creating a UIBezierPath object, but you never use it. Do that by calling CGContextAddPath( context, newPath.CGPath ), changing the variable name as needed in the two places you appear to the using a UIBezierPath.
Keep the call to setNeedsDisplayInRect: in your touch handler method. That tells the system to do the work to update your view using the drawing that your (yet to be implemented) drawRect: method draws.
I am trying to draw a straight line between two points in overlay view.
In MKOverlayView method, I think I am doing correctly but I don't understand why it's not drawing any lines...
Does anyone know why?
- (void)drawMapRect:(MKMapRect)mapRect zoomScale:(MKZoomScale)zoomScale
inContext:(CGContextRef)context
{
UIGraphicsPushContext(context);
MKMapRect theMapRect = [[self overlay] boundingMapRect];
CGRect theRect = [self rectForMapRect:theMapRect];
// Clip the context to the bounding rectangle.
CGContextAddRect(context, theRect);
CGContextClip(context);
CGPoint startP = {theMapRect.origin.x, theMapRect.origin.y};
CGPoint endP = {theMapRect.origin.x + theMapRect.size.width,
theMapRect.origin.y + theMapRect.size.height};
CGContextSetLineWidth(context, 3.0);
CGContextSetStrokeColorWithColor(context, [UIColor blueColor].CGColor);
CGContextBeginPath(context);
CGContextMoveToPoint(context, startP.x, startP.y);
CGContextAddLineToPoint(context, endP.x, endP.y);
CGContextStrokePath(context);
UIGraphicsPopContext();
}
Thank you for your help.
The line is being drawn using startP and endP which are CGPoint values but they are initialized using theMapRect which contains MKMapPoint values.
Instead, initialize them using theRect which you are converting from theMapRect using rectForMapRect.
Also, for the line width, you may want to scale it using the MKRoadWidthAtZoomScale function. Otherwise, a fixed line width of 3.0 will not be visible unless you are zoomed in very close.
The changed code would look like this:
CGPoint startP = {theRect.origin.x, theRect.origin.y};
CGPoint endP = {theRect.origin.x + theRect.size.width,
theRect.origin.y + theRect.size.height};
CGContextSetLineWidth(context, 3.0 * MKRoadWidthAtZoomScale(zoomScale));
Finally, instead of a custom MKOverlayView, why not use a MKPolylineView to avoid drawing lines manually?
I am currently drawing a UIImage within a UIBezierPath like so:
UIGraphicsBeginImageContextWithOptions(rect.size, NO, 0);
UIBezierPath *polygonPath = [UIBezierPath bezierPath];
CGPoint curPoint = [self originalPoint:[[drawArray objectAtIndex:0]CGPointValue]];
// set the starting point for the lines
[polygonPath moveToPoint:curPoint];
// go through each point in drawArray and add it to polygonPath
for(NSInteger i = 1; i < [drawArray count]; i++) {
curPoint = [self originalPoint:[[drawArray objectAtIndex:i]CGPointValue]];
// scale point
curPoint = CGPointMake(curPoint.x, curPoint.y);
[polygonPath addLineToPoint:curPoint];
}
[polygonPath closePath];
[polygonPath addClip];
[image drawAtPoint:CGPointZero];
It works great, however I'd like to have "smooth edges", slightly transparent, for the image, as I'm drawing it on top of another image... Right now the edges are pretty rough.
Thanks for your help!
As you are drawing on the image. So I suggest you to use following code...
Where YourImageis the UIImage on which you are drawing line.
[[UIColor colorWithPatternImage:YourImage] set];
For More Visit this reference
Hope, this will help you...
I have the following code the only seems to use the last colour for the whole line.....
I want the colour to be changing throughout this. Any ideas?
CGContextSetLineWidth(ctx, 1.0);
for(int idx = 0; idx < routeGrabInstance.points.count; idx++)
{
CLLocation* location = [routeGrabInstance.points objectAtIndex:idx];
CGPoint point = [mapView convertCoordinate:location.coordinate toPointToView:self.mapView];
if(idx == 0)
{
// move to the first point
UIColor *tempColor = [self colorForHex:[[routeGrabInstance.pointHeights objectAtIndex:idx] doubleValue]];
CGContextSetStrokeColorWithColor(ctx,tempColor.CGColor);
CGContextMoveToPoint(ctx, point.x, point.y);
}
else
{
UIColor *tempColor = [self colorForHex:[[routeGrabInstance.pointHeights objectAtIndex:idx] doubleValue]];
CGContextSetStrokeColorWithColor(ctx,tempColor.CGColor);
CGContextAddLineToPoint(ctx, point.x, point.y);
}
}
CGContextStrokePath(ctx);
The CGContextSetStrokeColorWithColor only changes the state of the context, it does not do any drawing. The only drawing done in your code is by the CGContextStrokePath at the end. Since each call to CGContextSetStrokeColorWithColor overrides the value set by the previous call the drawing will use the last color set.
You need to create a new path, set the color and then draw in each loop. Something like this:
for(int idx = 0; idx < routeGrabInstance.points.count; idx++)
{
CGContextBeginPath(ctx);
CGContextMoveToPoint(ctx, x1, y1);
CGContextAddLineToPoint(ctx, x2, y2);
CGContextSetStrokeColorWithColor(ctx,tempColor.CGColor);
CGContextStrokePath(ctx);
}
CGContextSetStrokeColorWithColor sets the stroke color in the context. That color is used when you stroke the path, it has no effect as you continue building the path.
You need to stroke each line separately (CGContextStrokePath).