drawing

问题 I have a bunch of data points that I would like to two-way bind to points on a canvas. The points assume larger y values are reflected in an upwards direction like most math graphs. How do I change the x,y origin of the canvas to the bottom left corner and reverse it's interpretation of the y coordinate? (I would like to stay in XAML) 回答1: <Canvas> <Canvas.LayoutTransform> <ScaleTransform ScaleX="1" ScaleY="-1" CenterX=".5" CenterY=".5" /> </Canvas.LayoutTransform> </Canvas> 回答2: I tried the

问题 I'm trying to animate a circle and just moving it horizontally which works fine. However while the circle is moving, I have to do a clearRect over that circle so that it redraws it self in the horizontal direction. When I do a clearRect it also makes the background have white box around so effectively its going to be one white horizontal line in the direction the circle is moving. Is there a way to clear the circle without clearRect? If I have to keep redrawing the background after clearRect

问题 First off this is for homework or... project. I'm having trouble understanding the idea behind how to draw the sound data waves on to a graph in Java for a project. I have to make this assignment entirely from scratch with a UI and everything so basically making a .wav file editor. The main issue I'm having is getting the sound data into the graph to be drawn. Currently I have a randomly generated array of values just being drawn right now. So far I have a mini-program running and validating

问题 I'm working on an HTML5 game. I need to draw tail lines in the canvas and check for intersections in the game, which is a Tron-style game. I'm actually using the drawLine() function from JCanvas, but JCanvas did not provide me a way to check for line intersection, I digged in the source and found the use the ctx object, and at the end of the function I'm using, I returned the object so I can use the ctx.isPointInPath() method to achieve what I need, but is not working, is returning false

问题 Is it possible to create a big white rectangle on the screen with just using the C# console and not an C# Forms Application? It should cover the whole Screen if possible. I know I have to use the System.Drawing and tried several steps, but none will actually print anything on my screen! 回答1: Method 1: Call the Windows API You need System.Drawing and System.Runtime.InteropServices . You may need to add project references to them. using System.Runtime.InteropServices; using System.Drawing; Add

问题 I have three questions actually: Is it better to draw an image on a bitmap or create a bitmap as resource and then draw it over a bitmap? Performance wise, which one is better? If I want to draw something transparent over a bitmap, how would I go about doing it? If I want to overlay one transparent bitmap over another, how would I do it? Sorry for the long list, but in the interest of learning, I would like to explore both the approaches. 回答1: I can't believe no one has answered this yet! A

问题 I have an interesting question. Imagine I have a lot of data changing in very fast intervals. I want to display that data as a table in console app. f.ex: ------------------------------------------------------------------------- | Column 1 | Column 2 | Column 3 | Column 4 | ------------------------------------------------------------------------- | | | | | | | | | | | | | | | ------------------------------------------------------------------------- How to keep things fast and how to fix

问题 How can I draw a line in XAML using a System.Drawing.Color ? A solution without a converter would be nice. XAML: <Line X1="10" Y1="10" X2="20" Y2="10" Stroke="{Binding Color}" StrokeThickness="4" /> Code: System.Drawing.Color Color = System.Drawing.Color.Black; 回答1: You need to bind a Brush to the Stroke property, in particular a SolidColorBrush, which accepts a color. However, you need to convert from System.Drawing.Color to System.Windows.Media.Color, e.g. by passing the R, G, and B values

问题 I would like to know how to draw a layer with some color [CGColorRef] in a window When i am trying to addSubLayer to my window , the application is exiting without showing any exception. 回答1: If your app is just quitting with no debug error, there still could be a message sent to some deallocated instance. Try turning on NSZombieEnabled by following the instructions here: http://www.codza.com/how-to-debug-exc_bad_access-on-iphone This will tell you when a bad message is sent. Further, if you

问题 I'm currently working on my own basic drawing app. So far, my app is working well but I noticed that my motion event doesn't seem to get all the X and Y axis points that are touched. When I move my finger across the screen, there is noticeable spaces between the circles. Only when I move my finger slowly does it capture all the points. Is there a way I can grab all the points or is there a way i can optimize it to be able to handle all the points? Here's how I'm doing it: setOnTouchListener