canvas

Rotation and Scaling controls are off after using setAngle() in Fabric.js

由 耗尽温柔 提交于 2020-01-21 18:54:19
问题 I want to let users rotate objects on the Fabric.js powered canvas, but limit their rotation to 90 deg increments. Idea is that as they rotate and then stop, the object would "snap" into place at the closest angle. This works okay by listening to "object:rotating", setting the closest angle, then calling object.setAngle(angleClosestTo90). However, once the object has been "snapped", the controls for scaling/rotating the image are off. You can still select them, but it's finicky - I guess the

Rotation and Scaling controls are off after using setAngle() in Fabric.js

由 拟墨画扇 提交于 2020-01-21 18:54:19
问题 I want to let users rotate objects on the Fabric.js powered canvas, but limit their rotation to 90 deg increments. Idea is that as they rotate and then stop, the object would "snap" into place at the closest angle. This works okay by listening to "object:rotating", setting the closest angle, then calling object.setAngle(angleClosestTo90). However, once the object has been "snapped", the controls for scaling/rotating the image are off. You can still select them, but it's finicky - I guess the

Line Width in Canvas

由 為{幸葍}努か 提交于 2020-01-21 17:24:45
问题 Well, if I draw a line with an odd value of lineWidth in HTML5 Canvas I get a blurred line and I know the reason for this problem. Now, I want to know the solutions to overcome this. I already know a solution for this and which i couldn't implement now. So, please comment on any other solution for this problem. My Solution : If you have to draw a line with an odd numbered width, then you will have to offset the center of your line by 0.5 up or down. That way rendering will happen at boundary

Hexo-Next提高加载速度

由 自古美人都是妖i 提交于 2020-01-21 16:45:34
Hexo作为纯静态博客最大的优点就是快，但要真正的快起来你可能需要做这些事情。 CDN加速 这里只是针对第三方静态文件的加速，修改 Next 主题配置文件 _config.yml 如下： #! --------------------------------------------------------------- #! DO NOT EDIT THE FOLLOWING SETTINGS #! UNLESS YOU KNOW WHAT YOU ARE DOING #! See: https://theme-next.org/docs/advanced-settings #! --------------------------------------------------------------- # Script Vendors. Set a CDN address for the vendor you want to customize. # Be aware that you would better use the same version as internal ones to avoid potential problems. # Remember to use the https protocol of CDN files when you enable

drawing a triangle on canvas

由 允我心安 提交于 2020-01-21 11:35:09
问题 I am having trouble drawing a triangle on a canvas. Triangle: equilateral triangle with 2 points on the x-axis. So what I was thinking: I start in the bottom right corner, move up to the next point, and then move to the last point in the lower left. Here is what I have: <!doctype html> <html lang="en"> <head> <meta charset= "UTF-8"> <script type="text/JavaScript"> function draw() { var canvas = document.getElementById('canvas'); if (canvas.getContext) { var ctx = canvas.getContext('2d'); var

Best canvas for drawing in wxPython?

由 南笙酒味 提交于 2020-01-21 09:03:54
问题 I have to draw a graph of elements composing a topological model of a physical network. There would be nodes and arches, and the latter could be unidirectional or bidirectional. I would like to capture the clicking events for the nodes and the arches (to select the element and show its properties somewhere), and the dragging events for the nodes (to move them around) and arches (to connect or disconnect elements). I've done some research and I've narrowed the alternatives down to OGL (Object

Canvas within a scrollable browser window (grab position)

由 ﹥＞﹥吖頭↗ 提交于 2020-01-21 09:02:52
问题 I have an issue when drawing in a canvas within a browser window that has a vertical scrollbar. The figures is at the correct position, and is possible to grab it around the canvas and make the connections, but this is only possible with the vertical scrollbar (of the browser window) fully up. When the window is scrolled down, the nodes can't be dragged any more, and even the cursor doest change when its hovering the node. I figured out that its possible to drag the node when scrolled down.

cursor:pointer on hover html5 canvas element

由 拥有回忆 提交于 2020-01-21 06:37:59
问题 is there anyway to do this to let the user know the element is clickable?. I have been using easeljs but haven't found anything related 回答1: You could use this: How to make clickable points in html5 canvas? and while the mouse is in that area, you can set: $('#canvasID').css('cursor','pointer') and $('#canvasID').css('cursor','auto') when it's not over it. 回答2: I am using Easeljs and to get a pointer cursor I use myObject.cursor = 'pointer' and stage.enableMouseOver(20); ( from the

Animating a “Wobbly Canvas” like in Discord's Login page?

由 喜欢而已 提交于 2020-01-21 04:53:04
问题 For reference, I'm talking about the dark-gray space in the upper left of Discord's Login Page. For anyone who can't access that link, here's a screenshot: It has a number of effects that are really cool, the dots and (darker shadows) move with the mouse, but I'm more interested in the "wobbly edge" effect, and to a lesser extent the "fast wobble/scale in" on page load (scaling in the canvas on load would give a similar, if not "cheaper" effect). Unfortunately, I can't produce much in the way

How to draw a circle sector on an html5 canvas?

由 99封情书 提交于 2020-01-21 02:53:45
问题 I'm trying to make a sort of pie-chart shape on a canvas element, however I can't seem to find any function that does this by itself. I only seem to be able to draw full circles and segments. Is there an easy way to do this? (See also: Wikipedia on circle terminology) 回答1: The following should work: context.moveTo(cx,cy); context.arc(cx,cy,radius,startangle,endangle); context.lineTo(cx,cy); context.stroke(); // or context.fill() with cx , cy being the center of the arc. 来源： https:/
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