I work on a UWP app where the user must be able to take a photo from the camera, and add details by drawing some shapes. I think the simplest way to do this is using the InkToolbar. So I've donwloaded the official sample: SimpleInk
But I don't see how to solve some of my needs:
add a background image to the InkCanvas: I would like get a BitmapImage containing the original photo and the items drawed by the user
=> is it possible to do this properly? or do I need to superpose the Image and the InkCanvas in the Grid and take a screenshot?
draw basic shapes like circles or rectangles: all the samples are based on hand drawing with different kinds of pencils
=> is there a way to draw shapes like circles or rectangles through this control? or what is the better way for allowing user to "draw" shapes easily?
I also looked at the Win2D samples Win2D-samples, but I didn't found a similar case.
Thanks in advance for your feedbacks!
add a background image to the InkCanvas: I would like get a BitmapImage containing the original photo and the items drawed by the user
The InkCanvas doesn't contain a background property directly. You can create an InkCanvas overlays a background image by using an Image control like the Basic inking with InkCanvas sample shows.
But if you need to get a new BitmapImage from original image with InkCanvas drawing you need to use the Win2D library. For more details and a completed demo please reference this thread.
draw basic shapes like circles or rectangles: all the samples are based on hand drawing with different kinds of pencils
For this, the UAP sample of Win2D-samples you mentioned above provided a demo for drawing a circle you can reference(same with rectangles like follows).
args.DrawingSession.DrawEllipse(155, 115, 80, 30, Colors.Black, 3);
args.DrawingSession.DrawRectangle(155, 115, 80, 30, Colors.Black);
The official Complex inking sample also provide the Insert a shape feature you can test and reference.
Related
In certain programs and applications, when I looked at their installation files they had some images only a few pixels say 40px in height and 1px in width.
I learned from that time that image files are used seamlessly to create textures for certain parts of their programs "window" or "form".
I would like to know how to recreate this in visual basic. Let's take a simple example to use: I have a panel and inside this panel I want the seamless texture to repeat so that when the user re-sizes the form the image isn't cropped or not visibly stretched.
Also take the example of the image below showing the title bar in iTunes.
(I have already tried searching examples of this, but I don't know what the method is called and online results focus mainly on the words "seamless" and "design", showing things like Illustrator)
Background image in Tile or Stretch mode
I am currently writing a program that requires a picture box with a transparent image to go over several pictureboxes. I have looked for hours now and found nothing useful. the program is a rubiks cube solver. each square is represented as a picturebox and the cube is shown in a net form. I cant upload images as my account is new but i have included an image of a rubiks cube in a net form. now imagine a semi transparent image going over some of the squares (pictureboxes) to represent a visual guide to the rotation about to be made in the solve process. If you need more info I will do my best and upload images and add code for better clarification if needed. If this is not possible is there any alternatives that I could attempt? Thankyou
I don't think what you want is possible. I was actually trying to solve the same problem about 2 days ago and to no avail. You can't have transparency to work with multiple pictureboxes on winforms. What you need to do is draw the images using Graphics like one over the other. Use 1 picturebox and do Graphics to overlay the picture on the picturebox. Or have the main picture as the form's background image and use pictureboxes, this was what I did. This is surely easier using WPF. Alternatively... Try to check this imaging SDK.
http://www.gdpicture.com/
This might help overlaying your images.
And this too, this is basically the one using 1 picturebox and overlaying using Graphics.
VB.NET Winforms: Overlay two transparent images
I am working on drag and drop activity for iPad. I have a rectangle PNG image (see the image named as obj2). When I drag obj1 only on the black portion of the rectangle then it should react.
if (CGRectIntersectsRect(obj1.frame, obj2.frame))
{
NSLog(#" hit test done!! ");
}
Right now, this piece of code takes hit test even on the transparent area. How to prevent that to happen?
For something as simple as your specific example (triangle and circle), the link that David Rönnqvist gives is very useful. You should definitely look at it to see some available tools. But for the general case, the best bet is clipping, drawing, and searching.
For some background, see Clipping a CGRRect to a CGPath.
First, create an alpha-only bitmap image. This is explained in the above link.
Next, clip your context to one of your images using CGContextClipToMask().
Now, draw your other image onto the context.
Finally, search the bitmap data for any colored pixels (see the above link for example code).
If any of the pixels colored, then there is some overlap.
Another, similar approach (which might actually be faster), is to draw each image into its own alpha-only CGBitmapContext. Then walk the pixels in each context and see if they ever are both >128 at the same time.
I want to create a bubbles like game in android and I'm not sure how to draw the graphics.
Should I use canvas ? Every bubble should be a bitmap or maybe an image view ?
Another thing, I want to be able to rotate / scale the bubbles.
I've tried with bitmaps and canvas but wasn't able to rotate the bubbles.
Image view for every bubble looks like a mess to me.
Your help is appreciated.
Thanks
If you want to make a game, I would suggest using a Canvas, and put the Canvas over most, or all, of your layout. Creating anything but the most basic game using the regular UI structures would be a nightmare.
It sounds like you've gotten to the point where you can load the bubble images and draw them to the canvas, which is good. As for rotating the bubbles, use this:
Matrix rotator = new Matrix();
rotator.postRotate(90);
canvas.drawBitmap(bitmap, rotator, paint);
That was from an answer to this SO question, which was more specifically about rotating bitmaps on a Canvas.
For more information on making games in Android, this book was pretty helpful for me.
Hope that helps!
I have been looking for the solution on the web for a long time. Most tutorials are fairly simple about adding shadow to a UIView. I also noticed that if we add a shadow to an UIImageView. The shadow shape could perfectly fit the shape of the content image if the image itself has alpha channel in it. Say for example, if the image is an animal with transparent background, the shadow shape is also the same as that animal (not a rectangle shadow as same as UIImageView frame).
But these are not enough. What I need to do is to add some changes to the shadow so it may have some rotation angle and compressed (squeezed or shift) effect so that looks like the sunlight comes from a certain spot.
To demonstrate what I need, I upload 2 images below, which I captured from the Google Map App created by Apple. You can imagine the Annotation Pin is an image which has the Pin shape, so the shadow is also "pin shaped", but it is not simply "offset" with a CGSize, you can see the top of the shadow is shifted right about 35 degrees and slightly squeezed the height.
When we tap and hold and pin, the shadow is also animated away from the pin, so I believe that such shadow can be made programmably.
The best shadow tutorial I can found so far is http://nachbaur.com/blog/fun-shadow-effects-using-custom-calayer-shadowpaths But unfortunately, that cannot make this effect.
If anyone know the answer or know any better words to search for, please let me know. Thank you.
(Please note that the shape of the image is dynamic in the App, so using any tool like Photoshop to pre-render the shadow is not an option.)
In order to create dynamic effects like this, you have to use Core Graphics. It's incredibly powerful once you know how to use it. Basically you need to set a skew transform on the context, set up a shadow and draw the image. You will probably have to use transparency layers as well.
It doesn't sound like you can use CALayer shadows, since that is meant to solve a specific use-case. The approach Apple takes with the pin marks on the map is to have two separate images that are created ahead of time (e.g. in Photoshop) and they position them within the map relative to a reference point.
If you really do need to do this at run-time, it should still be possible by using either Core Graphics or ImageKit. To get a blurred shadow appearance, you can use the kCICategoryBlur CIFilter. You can then convert the image to grayscale. And to get that compressed look you just need to resize and skew the image.
Once you have two separate images, you can either take the CGImageRef for the shadow image and can set that as the content of another sublayer, or you can add it as a separate view.
If you know what all the shapes are, you could just render a shadow image in Photoshop or something.