public override void DrawInContext(CGContext context)
{
base.DrawInContext(context);
nfloat size = NMath.Min(Bounds.Size.Width, Bounds.Size.Height);
CGAffineTransform transform = AffineTransform;
nfloat xTranslate = 0;
nfloat yTranslate = 0;
if (Bounds.Size.Width < Bounds.Size.Height)
{
yTranslate = (Bounds.Size.Height - size) / 2f;
}
else
{
xTranslate = (Bounds.Size.Width - size) / 2f;
}
transform.Translate(xTranslate, yTranslate);
nfloat strokeWidth = StrokeFactor * size;
nfloat checkBoxInset = InsetFactor * size;
// Create the outer border for the check box.
nfloat outerDimension = size - 2 * checkBoxInset;
var checkBoxRect = new CGRect(checkBoxInset, checkBoxInset, outerDimension, outerDimension);
checkBoxRect = transform.TransformRect(checkBoxRect);
// Make the desired width of the outer box.
context.SetLineWidth(strokeWidth);
// Set the tint color of the outer box.
context.SetStrokeColor(TintColor);
// Draw the outer box.
context.StrokeRect(checkBoxRect);
// Draw the inner box if it's checked.
if (Checked)
{
nfloat markInset = MarkInsetFactor * size;
nfloat markDimension = size - 2 * markInset;
var markRect = new CGRect(markInset, markInset, markDimension, markDimension);
markRect = transform.TransformRect(markRect);
context.SetFillColor(TintColor);
context.FillRect(markRect);
}
}
void RenderLinearGradient(CGContext graphics, CGRect pathBounds, LinearGradientBrush brush)
{
using (CGColorSpace rgb = CGColorSpace.CreateDeviceRGB())
{
CGColor[] colors = new CGColor[brush.GradientStops.Count];
nfloat[] locations = new nfloat[brush.GradientStops.Count];
for (int index = 0; index < brush.GradientStops.Count; index++)
{
Color color = brush.GradientStops[index].Color;
colors[index] = new CGColor(new nfloat(color.R), new nfloat(color.G), new nfloat(color.B), new nfloat(color.A));
locations[index] = new nfloat(brush.GradientStops[index].Offset);
}
CGGradient gradient = new CGGradient(rgb, colors, locations);
if (brush.Transform != null)
{
CGAffineTransform transform = (CGAffineTransform)brush.Transform.GetNativeObject();
// TODO: This does not adequately work.
// There is no real SpreadMethod in iOS.
pathBounds = transform.TransformRect(pathBounds);
}
graphics.DrawLinearGradient(gradient, new CGPoint(pathBounds.Left + brush.StartPoint.X * pathBounds.Width,
pathBounds.Top + brush.StartPoint.Y * pathBounds.Height),
new CGPoint(pathBounds.Left + brush.EndPoint.X * pathBounds.Width,
pathBounds.Top + brush.EndPoint.Y * pathBounds.Height),
CGGradientDrawingOptions.DrawsBeforeStartLocation |
CGGradientDrawingOptions.DrawsAfterEndLocation);
}
}
public void SetClip(RectangleF rectangle)
{
RewindTransform();
RewindClip();
clipPath = null;
clipBounds = currentTransform.TransformRect(rectangle.ToNS());
ApplyClip();
ApplyTransform();
}
public void TransformRect()
{
var transform = new CGAffineTransform(1, 2, 3, 4, 5, 6);
var rect = transform.TransformRect(new CGRect(4, 5, 6, 7));
Assert.AreEqual((nfloat)24, rect.X, "X");
Assert.AreEqual((nfloat)34, rect.Y, "Y");
Assert.AreEqual((nfloat)27, rect.Width, "Width");
Assert.AreEqual((nfloat)40, rect.Height, "Height");
}
public object GetImageFromUri(FileUri imageUri, int targetWidth, int targetHeight, int rotation)
{
using (Stream stream = GetFileSystem().OpenFile(imageUri, UniversalFileMode.Open, UniversalFileAccess.Read, UniversalFileShare.Read))
{
CGImageSource source = CGImageSource.FromUrl(imageUri.ToNSUrl());
CGImageOptions options = new CGImageOptions();
options.ShouldCache = false;
var props = source.CopyProperties(options, 0);
int imageWidth = ((NSNumber)props["PixelWidth"]).Int32Value;
int imageHeight = ((NSNumber)props["PixelHeight"]).Int32Value;
int scale = 1;
while (imageWidth / scale / 2 >= (nfloat)targetWidth &&
imageHeight / scale / 2 >= (nfloat)targetHeight)
{
scale *= 2;
}
stream.Seek(0, SeekOrigin.Begin);
UIImage image = UIImage.LoadFromData(NSData.FromUrl(imageUri.ToNSUrl()), scale);
if (rotation != 0)
{
float radians = rotation * (float)Math.PI / 180f;
CGRect imageFrame = new CGRect(0, 0, image.Size.Width, image.Size.Height);
CGAffineTransform t = CGAffineTransform.MakeRotation(radians);
imageFrame = t.TransformRect(imageFrame);
CGSize rotatedSize = new CGSize(imageFrame.Width, imageFrame.Height);
UIGraphics.BeginImageContext(rotatedSize);
using (CGContext context = UIGraphics.GetCurrentContext())
{
context.TranslateCTM(rotatedSize.Width / 2, rotatedSize.Height / 2);
context.RotateCTM(-radians);
context.ScaleCTM(1.0f, -1.0f);
image.Draw(new CGRect(-image.Size.Width / 2, -image.Size.Height / 2, image.Size.Width, image.Size.Height));
image = UIGraphics.GetImageFromCurrentImageContext();
}
UIGraphics.EndImageContext();
}
return(image);
}
}
CGAffineTransform GetImageTransformAboutCenter(float angleDegrees, CGSize imageSize)
{
// Create a tranform that will rotate our image about its center
CGAffineTransform transform = CGAffineTransform.MakeIdentity( );
// setup our transform. Translate it by the image's half width/height so it rotates about its center.
transform.Translate(-imageSize.Width / 2, -imageSize.Height / 2);
transform.Rotate(angleDegrees * Rock.Mobile.Math.Util.DegToRad);
// now we need to concat on a post-transform that will put the image's pivot back at the top left.
// get the image's dimensions transformed
CGRect transformedImageRect = transform.TransformRect(new CGRect(0, 0, imageSize.Width, imageSize.Height));
// our post transform simply translates the image back
CGAffineTransform postTransform = CGAffineTransform.MakeIdentity( );
postTransform.Translate(transformedImageRect.Width / 2, transformedImageRect.Height / 2);
// now multiply the transform and postTranform and we have our final transform to use
return(CGAffineTransform.Multiply(transform, postTransform));
}
