Adding Image to Xaml not rendering with given margin - xaml

for (int i = 0; i < length; i++)
{
Image img1 ;
img1 = null;
img1= new Image();
img1.Height = snhei;
img1.Width = snwid;
BitmapImage BitImg = new BitmapImage(new Uri("/Assets/midtail.png", UriKind.Relative));`
img1.VerticalAlignment = VerticalAlignment.Top;
img1.HorizontalAlignment = HorizontalAlignment.Left;
img1.Source = BitImg;
img1.Stretch = Stretch.Fill;
img1.Name = "mid" + i.ToString() ;
img1.Margin = new Thickness(image_width*i, 0, 0, 0);
stackp.Children.Add(img1);
}
after running i get first image at 0,0
then it is render the one image_width below

The problem is your container. The StackPanel will, as it name indicates, try to stack the images. Then you apply the margin, moving the picture farther away.
You have two solutions, depending on what you want:
If you just want the images to be displayed side by side, set the Orientation property of your StackPanel to Horizontal. Then, remove your line of code that sets the margin, since the positioning is automatically handled by the StackPanel
If you still want to position the pictures manually, then you have to use another type of container. Replace your StackPanel by a Canvas or a Grid.

Related

Camera position cause objects to disappear

I'm developing an app with blazor client-side and I need to render a 3D scene.
I have an issue and I guess it is material-related.
I have a composition of parallelepipeds where one of them is fully opaque and the others are transparent.
Depending on the camera angle, the transparent ones completely disappear:
Example where everything is visible:
Example with 2 missing:
Example with all missing:
Code for transparent parallelepipeds
var geometry = new THREE.CubeGeometry(item.xDimension * _scene.normalizer, item.yDimension * _scene.normalizer, item.zDimension * _scene.normalizer);
var material = new THREE.MeshBasicMaterial();
var box = new THREE.Mesh(geometry, material);
box.material.color = new THREE.Color("gray");
box.material.opacity = 0.8;
box.material.transparent = true;
Code for the camera:
var camera = new THREE.PerspectiveCamera(60, width / height, 0.1, 100);
camera.position.set(1.3, 1.3, 1.3);
camera.lookAt(0, 0, 0);
I'm using OrbitControls and every object size is between 0 an 1 (_scene.normalizer is for that purpose)
Do you know why this is happening?
Edit:
I found it being a material depth function issue. Do you know which should I use?
Thanks,
Transparency is tricky with WebGL because a transparent object writes to the depthmap, and then the renderer assumes that subsequent objects behind it are occluded so it skips drawing them. You could avoid this by playing with the material's .depthTest and .depthWrite attributes (see the docs):
box.material.color = new THREE.Color("gray");
box.material.opacity = 0.8;
box.material.transparent = true;
box.material.depthWrite = false;

EaselJS line draw with unnecessary multiple dots issues

While drawing a line on canvas, it creates multiple dots within the line. I am using easelJS for canvas drawing. Please refer the attached screenshot.
Code for line draw is as below.
Line with multiple dots
scope.init = function(){
stage = new createjs.Stage(element[0].id);
stage.enableDOMEvents(true);
createjs.Touch.enable(stage);
shellWrapper = new createjs.Container();
shellWrapper.id = mainContainerId;
shellWrapper.hitArea = new createjs.Shape(new createjs.Graphics().f('#000').dr(0,0,cacheWidth,cacheHeight));
shellWrapper.cache(0,0,cacheWidth,cacheHeight); // Cache it.
stage.addChild(shellWrapper);
drawing = new createjs.Shape();
shellWrapper.addChild(drawing);
stage.update();
}
scope.mouseDown = function(event) {
oldX = event.stageX;
oldY = event.stageY;
shellWrapper.addEventListener('pressmove', function(evt){
drawing.graphics.beginStroke(color)
.setStrokeStyle(size, 'round')
.moveTo(oldX, oldY)
.lineTo(evt.stageX, evt.stageY);
oldX = evt.stageX;
oldY = evt.stageY;
shellWrapper.updateCache(erase?'destination-out':'source-over');
drawing.graphics.clear();
stage.update();
});
};
This happens because a single line has its limits rounded, so it actually look like this:
The rounded edge goes a little bit (depending on stroke width) out of the line boundary so it gets over the past line drawn. This line overlay causes your drawing to look like it has small circles, but it does not, and thats because you're using a semi transparent color on the stroke.
To solve the issue, make the stroke color opaque and add transparency to the whole drawing by using myDisplayObj.alpha = 0.5;
This way individual lines will be fully opaque in relation to each other but they will be semi transparent relative to other display objects in the scene.

Copying three JS rendered canvas to another canvas fails on desktop Safari

I need to copy a canvas rendered with three.js to another canvas by using the drawImage method of the canvas context.
ctx.drawImage(renderer.domElement, 0, 0);
It works like expected on Chrome and Firefox but doesn't work at all on my desktop Safari. I tried to specify the texture format but it didn't make any difference. Anyone knows the trick?
Here's a codepen with the three.js script.
http://codepen.io/anon/pen/BNvzMJ
This code works on safari but it flips the image upside down and the framerate goes down by 50% so it's definitely not ideal.
http://codepen.io/anon/pen/VLqmRO
var gl = renderer.getContext();
var width = renderer.domElement.width;
var height = renderer.domElement.height;
var size = width * height * 4;
var pixels = new Uint8Array(size);
var image = ctx.createImageData(width, height);
gl.readPixels(0, 0, width, height, gl.RGBA, gl.UNSIGNED_BYTE, pixels);
for (var i = 0; i < size; i++) {
image.data[i] = pixels[i];
}
ctx.putImageData(image, 0, 0);
Why not use canvas.getImageData?
var width = renderer.domElement.width;
var height = renderer.domElement.height;
var imgData = gl.getImageData(0, 0, width , height);
ctx.drawImage(imgData, 10, 70);

JPanel resize and scroll errors

I use a text area with variable hight and some other things (a combo box in the sample code) filling the window width.
The following error happens:
- When using "innerPanel.setPreferredSize", the scroller does not appear when the text area becomes higher than the window by typing line feeds into the text area or when resizing the window vertically.
- When not using "innerPanel.setPreferredSize", (as shown commented in the sample code below), the used swing elements enlarge horizontally when resizing the window width, but do never shrink horizontally.
JPanel innerPanel = new JPanel(new GridBagLayout());
JTextArea editArea = new JTextArea();
editArea.setLineWrap(true);
GridBagConstraints gbc = new GridBagConstraints();
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.weightx = 1.;
innerPanel.add(editArea, gbc);
JComboBox combo = new JComboBox();
gbc.gridy = 1;
innerPanel.add(combo, gbc);
JScrollPane scroller = new JScrollPane(innerPanel,
JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
//innerPanel.setPreferredSize(new Dimension(50, 50));
JPanel outerPanel = new JPanel(new BorderLayout());
outerPanel.add(scroller);
frame.setContentPane(outerPanel);

SL4: How do I change the scale w/o scrolling the canvas?

We have a large canvas contained in a scrollviewer. The user can move the canvas by dragging with the mouse, or using the scrollbars.
How can we change the zoom (scale) in the scrollviewer while keeping the current center point?
I think the issue is getting the correct CenterX and CenterY for the ScaleTransform:
var st = MapCanvas.RenderTransform as ScaleTransform;
if (null != st)
{
st.CenterX = point.X;
st.CenterY = point.Y;
st.ScaleX = st.ScaleY = scale;
}
Thanks for any hints...
It's been a while since I looked at transforms, but you might want to try setting the RenderTransformOrigin of MapCanvas to new Point(0.5, 0.5) (or set it in XAML)