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Changes between Version 10 and Version 11 of Examples/ParaviewAnimating

Timestamp:: 06/15/18 10:34:58 (6 years ago)
Author:: Herwig Zilken
Comment:: --

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Examples/ParaviewAnimating

-              v10
+              v11
 == Basic Concept ==
 The basic concept of how to animate "something", in this case the rendered !ParaView scene, is quite easy to understand. The central element of any animation is a timeline with a start and end time and a mechanism to determine a number of descrete timesteps (frames). All this is implemented in the Python class paraview.simple.!AnimationScene.
+The basic concept of how to animate "something", in this case parameters (so called properties) of the !ParaView scene, is quite easy to understand. The central element of any animation is a timeline with a start and end time and a mechanism to determine a number of descrete timesteps (frames). in ParaView all this is implemented in the Python class paraview.simple.!AnimationScene.
 Within the time interval defined in the timeline, properties of the scene can be changed.
 In the !ParaView GUI this concept is reflected by so called "tracks" (or "cues") in the Animation View. Basically, each track defines the temporal change of one (or more) properties of the scene.
 …
 In !ParaView-Python, different kinds (classes) of tracks/cues are available. We will deal with four of them, which are implemented in the following Python classes:
 * paraview.simple.!KeyFrameAnimationCue: basic cue to animate general properties of objects (readers, sources, filters) in the render pipeline
 * paraview.simple.!CameraAnimationCue: cue to change camera parameters (e.g. position, focal point, up direction, view angle)
+* paraview.simple.!CameraAnimationCue: cue to change camera parameters (e.g. position, focal point, up direction, view angle, parallel scale)
 * paraview.simple.!PythonAnimationCue: cue to execute a Python script at a certain point in time
 * paraview.simple.!TimeAnimationCue: cue to determine what data timesteps are loaded depending on the animation clock time
+In general, each cue is connected to one or more properties of a ParaView object and has a number of keyframes attached to it, each defining certain values valid for a specific point in time. Therefore the key elements :) of a keyframe are keytime and keyvalues. The value(s) of the referred property is set to the keyvalues at the specified keytime. The most types of keyframes have the ability to interpolate keyvalues from one keyframe to the next. Specifically these are paraview.simple.!CameraKeyFrame, paraview.simple.!CompositeKeyFrame, paraview.simple.!ExponentialKeyFrame, paraview.simple.!RampKeyFrame and paraview.simple.!SinusoidKeyFrame.
+In general, each cue is connected to one or more properties of a !ParaView object and has a number of keyframes attached to it, each defining certain values valid for a specific point in time. Therefore the key elements :) of a keyframe are !KeyTime and !KeyValues. The value(s) of the referred property is set to the keyvalues at the specified keytime. The most types of keyframes have the ability to interpolate keyvalues from one keyframe to the next (se below).
 In the next paragraphs we are going to explain the basic mechanisms of the relevat Python classes and we give examples of typical use cases.
 == !AnimationScene ==
 The !AnimationScene is responsible to steer the animation clock time.
 For this purpose, the !AnimationScene has a !StartTime, an !EndTime, and a mechanism to calculate the discrete points in time between !StartTime and !EndTime. These descrete timesteps are determined by the Mode (called !PlayMode in Python) of the !AnimationScene. Three different PlayModes are avilable:
+For this purpose, the !AnimationScene has a !StartTime, an !EndTime, and a mechanism to calculate the discrete points in time between !StartTime and !EndTime. These descrete timesteps are determined by the Mode (called !PlayMode in Python) of the !AnimationScene. Three different !PlayModes are available:
 * 'Sequence': the timesteps are defined by the property !NumberOfFrames
 * 'Snap To !TimeSteps': only useful if you have time dependent data. The descrete timesteps are determind by the timesteps of the data. The !AnimationScene has knowledge about the available data timesteps by the help of a seperate object, the !TimeKeeper.
 * '!RealTime': given a specified duration, the timesteps are calculated on the fly (while rendering) in order to achieve that the animated sequence will take this duration. This mode is not useful for typical Python scripting, though.
+* 'Snap To !TimeSteps': only useful if you have time dependent data. The descrete timesteps are identical to the timesteps of the data. The !AnimationScene has knowledge about the available data timesteps by the help of a seperate object, the !TimeKeeper.
+* '!RealTime': given a specified duration, the timesteps are calculated on the fly (while rendering) in order to guarantee that the animated sequence will take this duration. This mode is not useful for typical Python scripting, though.
 Important properties of !AnimationScene:
 …
 #!python
 from paraview.simple import *
+renderView = GetActiveViewOrCreate('RenderView')
 animationScene = GetAnimationScene()
 animationScene.StartTime = 0
 …
 animationScene.PlayMode = 'Sequence'
 animationScene.GoToFirst()
+i = 0
 while True:
+   # render scene
+   # safe image
+   imageName = "image_%04d.jpg" % (i)
+   i = i + 1
+   renderView.Update()
+   SaveScreenshot(imageName, renderView, ImageResolution=[1920, 1080])
    if animationScene.AnimationTime == animationScene.EndTime:
       break
 …
 #!python
 from paraview.simple import *
+renderView = GetActiveViewOrCreate('RenderView')
 animationScene = GetAnimationScene()
 animationScene.PlayMode = 'Snap To TimeSteps'
 animationScene.GoToFirst()
+i = 0
 while True:
+   # render scene
+   # safe image
+   imageName = "image_%04d.jpg" % (i)
+   i = i + 1
+   renderView.Update()
+   SaveScreenshot(imageName, renderView, ImageResolution=[1920, 1080])
    if animationScene.AnimationTime == animationScene.EndTime:
       break
 …
 == Key Frames ==
 Before we start our explantion of cues, we give an overview about keyframes, as keyframes are an integral part of cues. Keyframes define what value(s) a cue passes to the property of the connected pipeline object at a give point in time.
 Without keyframes, a cue is more or less useless (with the exception of the !TimeAnimationCue, see below). A cue stores the list of attached keyframes in its KeyFrame property.
+Without keyframes, a cue is more or less useless (with the exception of the !TimeAnimationCue, see below). A cue stores the list of attached keyframes in its !KeyFrame property.
 The two basic keyframe classes are:
 …
 As already mentioned, a !KeyFrameAnimationCue connects the property of a pipeline object to the cue.
 This connection is defined via the attributes !AnimatedProxy (proxy of the pipeline object) and !AnimatedPropertyName (name of the connected property), though typically you do not have to set these attributes on your own. Instead they are set when constructing a !KeyFrameAnimationCue by calling !GetAnimationTrack(...) (see use case below).
 Similar to the !AnimationScene, every cue also has the properties !StartTime and !EndTime. Typically these properties do not have the identical values as the corresponding ones of !AnimationScene. When !TimeMode is set to 'Normalize', the start and end time of the animation scene is linearly interpolated to the interval ![0,1]. But don't care, these values are the defaults anyhow.
+Similar to the !AnimationScene, every cue also has the properties !StartTime and !EndTime. Typically these properties do not have to be identical to the corresponding ones of !AnimationScene. When !TimeMode is set to 'Normalize' (which is the default), the start and end time of the animation scene is linearly interpolated to the interval ![StartTime, EndTime]. Default values are StartTime=0 and EndTime=1.
 === !KeyFrameAnimationCue Use Case ===