![]() ![]() However, you may wish to optimize several discrete molecular structures at the same time and in relation to each other. ChemDoodle 3D therefore will optimize molecular structures separately and individually as you are editing them. this function is sent a parameter, delta, that specifies the amount of time since the last call in millisecondsĬhildOfAnimatorCanvas.Most small molecule force fields are optimized for describing individual discrete molecular structures. So let's take an in-depth look into how to implement the nextFrame() function: // we define the nextFrame() function of the child class This way, it can provide the nextFrame() function with the real amount of time that has passed since it was last called, allowing you to correctly update the scene in time. ![]() Therefore, in addition to the AnimatorCanvas class maintaining a timer, it also keeps track of the last time a frame was painted. This problem is compounded on slow processors, such as on some mobile devices. Secondly, we are assuming that the computer instantly updates and redraws the frame, but the computer actually needs to do work to update the scene and repaint the frame, so this adds to lag between frame repaints. Sometimes the timeout will be 30ms and sometimes the timeout will be 35ms. It will call a repaint on average about every 33ms. ![]() The first reason is that the timer is accurate, but it is not precise. Well there are two reasons why this is not true in reality. Given a perfect world, each repaint would be spaced exactly 33ms apart and we would know exactly how much time had passed simply by logging the number of repaint calls within a period. When we tell the AnimatorCanvas class to repaint every 33ms, it will try to achieve this as closely as possible. To adequately describe the nextFrame() function, we need to briefly discuss animation theory. Lastly there is an abstract function that needs to be defined in all children of AnimatorCanvas, called nextFrame(). There is also a function, AnimatorCanvas.isRunning(), that will return true if the animation is currently running and false otherwise. There are two control functions, AnimatorCanvas.startAnimation() and AnimatorCanvas.stopAnimation() that simply just start and stop the animation, respectively. This value is set to 33ms by default, which specifies that the component attempt to achieve a repaint every 33ms, or a framerate of about 30fps. There is one control variable, AnimatorCanvas.timeout, that defines the number of milliseconds between frame repaints, and will define a general framerate. ![]() Let's begin by analyzing the variables of the AnimatorCanvas class. Extending canvases is discussed on the last page, and if you have not reviewed it yet, now is a good time to do so. To create your own animations, all you have to do is extend the AnimatorCanvas class. The AnimatorCanvas class implements the necessary framework to produce high quality animations. Well, no worries, the ChemDoodle Web Components library contains an abstract AnimatorCanvas class that already handles this all for you! You can already see the ChemDoodle Web Components' animation framework in motion with the RotatorCanvas class. You need to implement a timer, and keep track of the elapsed time between frames as well as put together a framework to handle the animation. Animations are very difficult to program. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |