AspectFill - clip only one side - xamarin

I would like only the bottom part of the image to get clipped, is that possible? Currently, equal portions of the image get clipped at the top and at the bottom.
I tried setting VerticalOptions to Start, but had no success.
The red rectangles represent the screen and the blue rectangles represent the image that needs clipping. The top figure shows the current state and the bottom figure the desired state.

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Xcode Image Slicing Not Working with Gradients?

I have PNG images with rounded corners, inner shadows and a fill gradient, that I thought I could slice in Asset Catalogs horizontal and vertically. But no matter what I try, the gradient slice doesn't stretch or tile as I expected. With Xcode 9.1.
The gradient is not copied (although the inner shadow is), and in IB and the simulator, there are just two bars and no gradient.
What am I missing?
Here are the original image:
Here's how I sliced them:
And what they looked like in IB:
And here's what it looks like in IB (with the colors reversed in the simulator (with a red view and another similar image as background without any gradient) and device.
The center is the part that is getting tiled. You defined a 1x1 square that’s getting repeated on the interior of your image in order to make the image fill the space you defined, which isn’t your stated goal. What you can do is change your center to Stretches, and increase the center’s height and width to take up everything in your image that doesn’t include your rounded corners end caps.

put partly transpared photo on top of panorama

What is it nessesary to do if I want to see just black edges from background image in image placed on top?
Here in the picture is what I want to create.
You can see there are edges from background panorama mountains in picture on top.
Any ideas, please?
Does your background image already contain black edges? Then try this:
Swap the layers so that the background image is the top layer;
Select that layer which is now on top;
Select All;
Using the Select by Color tool, hold down Ctrl and click any of the black pixels to deselect all black edges and keep everything else selected (if your background image is JPEG then you will probably have to adjust the tool tolerance);
Delete the selected area.

iText - Image border width changes based upon image

I'm adding borders to various images in a .pdf document. The borders all have the same width, but in the .pdf the borders have different widths. It is more pronounced as the width of the border increases.
Also, is there a way to move the border outside of the image, so that it is not covering any of the image using the methods of the image class? I realize I can first put a filled rectangle and then add the image on top of the rectangle as an option. Just curious as to if this can be done with methods from the Image class.
Here is the code snippet
magazine.open();
canvas = pdfw.getDirectContent();
image = Image.getInstance("a.JPG");
image.setBorder(Rectangle.BOX);
image.scaleAbsolute(200,200);
image.setBorderWidth(50);
image.setAbsolutePosition(50,10);
//canvas.addImage(image);
magazine.add(image);
image = Image.getInstance("b.jpg");
image.setBorder(Rectangle.BOX);
image.scaleAbsolute(200,200);
image.setBorderWidth(50);
image.setAbsolutePosition(50,230);
//canvas.addImage(image);
magazine.add(image);
I fear you'll have to work with the workaround you described.
There are two ways to define a border for an image:
image.setUseVariableBorders(false);
This is the default. This is what you have (even though you aren't calling the method explicitly).
In this case, the thickness of the border is distributed in a way that half of the line width is inside the rectangle and half of the line width is outside of the rectangle. Maybe that's what's causing the effect that the difference you notice is more pronounced as the border width increases.
Then there is:
image.setUseVariableBorders(true);
Now the borders will be drawn inside the area needed for the image. This is useful for tables (both PdfPCell and Image are subclasses of the Rectangle class where these methods are defined), but I fear it doesn't help you in the case of images.
So your best chance is to add the border using a workaround.

Cocoa Resolution Independent Button Graphic

I'm trying to create a graphic in Sketch (a vector-based graphic design application). I export to PDF and this is what my original graphic looks like:
But when I set it as the image of an NSButton, it gets drawn like this:
Why does this occur? The right and bottom edges in particular are altered a lot. I'm not sure if this is a Cocoa drawing issue or an issue with my original graphic.
The problem is with (mis)alignment with the pixel grid and anti-aliasing. It looks like you've scaled the image so that the borders on the left, right, and bottom are roughly one pixel in thickness. However, the right and bottom borders are straddling the boundary between pixels. The result is that they contribute half their "darkness" to the pixel on one side of the boundary and the other half to the pixel on the other side of the boundary.
You should tweak either the proportions of the image or the size at which you're drawing it to avoid that particular alignment. It looks as though it's being rendered as roughly 10.5 pixels wide. You want it to be either 10 pixels or 11 pixels wide, so the right edge corresponds more closely to a pixel column.

Changing the view "center" of an html5 canvas

If have an image which is 1024x1250 and a canvas element that is 600x800, I can draw the image to the canvas centered such that the canvas is essentially a smaller view port of the larger image. I then want to allow that center point to move, thus creating the illusion that the viewport is viewing a different portion of the image.
Right now I've done this in sort of a hokey way where I redraw the portion of the image I want to see to the canvas, but I get this feeling that this isnt optimal. Is there a way to render the whole image to the canvas and then somehow "transform" my current center point so this view shift happens behind the scenes hopefully in some native layer?
You can add transformations to the context before drawing any image (rotation, scaling, translation...). What you need is the function context.translate(x,y).
Then, you only need to draw your image at (0,0)
For example, to display the bottom right portion of your image:
ctx.translate (-424, -450);
ctx.drawImage (image, 0, 0);
You can check this link https://developer.mozilla.org/en-US/docs/Web/Guide/HTML/Canvas_tutorial/Transformations to see a lot of examples on context transformation.

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