::New();
... // filling the UG
// Adding UG as block to vtkMultiBlockDataSet
mainMB->SetBlock(i, UG);
}
// Set the output format
vtkMultiBlockDataSet *outputMB = vtkMultiBlockDataSet::SafeDownCast(
outInfo->Get(vtkMultiBlockDataSet::DATA_OBJECT()));
// Make shallow copy of the output
outputMB->ShallowCopy(mainMB);
return 1;
}
```
The plugin performs very nicely, however, in my data source the data is time dependant. Now I am able to read and set as output **a single time slice** (I am using **IntVectorProperty** to specify which one) as **vtkMultiBlockDataSet**.
At the moment I’ve included **vtkXMLMultiBlockDataWriter** withing the plugin code to write the .vtm (and belonging.vtu files) for each time slice locally on my PC which I then manually open them in ParaView. ParaView then enables me to use each .vtm as a frame and I can play a very nice animation-like overall display of the (2D) data . If possible I would like to reproduce the same thing within the plugin itself (getting data directly to ParaView, without VTM writer in-between).
Is there a way to set the plugin to output multiple vtkMultiBlockDataSets as if I opened a set of .vtm files?
I realize there is a **SetNumberOfOutputPorts** option but this doesn’t come into account for me as only **after** plugin execution it is known how many time slices are present in the data source I’m working with and so far I haven’t found out any way to dynamically set the number of output ports.
Any help in this regard is highly appreciated. Thanks in advance.
---
### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [February 11, 2020, 2:48am UTC](https://discourse.paraview.org/t/paraview-plugin-setting-multiple-vtkmultiblockdatasets-as-output/3542/2 "2020-02-11T02:48:44Z")
Your multiblock design is not adapted to timesteps.
You will have to implement an actual timesteps-aware reader. See here :
[https://vtk.org/Wiki/VTK/Time\_Support](https://vtk.org/Wiki/VTK/Time_Support)
[https://vtk.org/Wiki/VTK/Tutorials/New\_Pipeline](https://vtk.org/Wiki/VTK/Tutorials/New_Pipeline)
and
`VTK/IO/XML/vtkXMLReader.cxx`
---
### Author:  [@penkod](https://discourse.paraview.org/u/penkod)
#### Post date: [February 13, 2020, 9:41am UTC](https://discourse.paraview.org/t/paraview-plugin-setting-multiple-vtkmultiblockdatasets-as-output/3542/3 "2020-02-13T09:41:38Z")
Thank you, Mathieu, for fast answer. This gave me more insight into this matter. However, I have an issue getting the time steps recognized by ParaView GUI (the frame buttons (“play” etc.) on top of the ParaView GUI). By default I am noticing that there are 10 time steps: [0, 0.111111, 0.222222, 0.333333, …, 1.0].
I am setting
```
myPlugin::myPlugin()
{
// Time support:
this->TimeStep = 0;
this->TimeStepRange[0] = 0;
this->TimeStepRange[1] = 0;
this->NumberOfTimeSteps = 0;
this->TimeSteps = NULL;
}
int myPlugin::RequestInformation(vtkInformation *request,
vtkInformationVector **vtkNotUsed(inputVector),
vtkInformationVector *outputVector)
vtkInformation* outInfo = outputVector->GetInformationObject(0);
outInfo->Remove(vtkStreamingDemandDrivenPipeline::TIME_STEPS());
outInfo->Remove(vtkStreamingDemandDrivenPipeline::TIME_RANGE());
if (!outInfo->Has(vtkStreamingDemandDrivenPipeline::TIME_RANGE()))
{
this->NumberOfTimeSteps = 15; // hardcoded for testing purposes
this->TimeSteps = new double[this->NumberOfTimeSteps];
// setting testing set of time step values
for (int step = 0; step < this->NumberOfTimeSteps; step++)
this->TimeSteps[step] = (double)step*2.1;
double tRange[2];
tRange[0] = this->TimeSteps[0];
tRange[1] = this->TimeSteps[this->NumberOfTimeSteps - 1];
this->TimeStepRange[0] = tRange[0];
this->TimeStepRange[1] = tRange[1];
outInfo->Set(
vtkStreamingDemandDrivenPipeline::TIME_STEPS(),
this->TimeSteps,
this->NumberOfTimeSteps);
outInfo->Set(vtkStreamingDemandDrivenPipeline::TIME_RANGE(),
tRange, 2);
}
```
The
```
outInfo->Set(
vtkStreamingDemandDrivenPipeline::TIME_STEPS(),
this->TimeSteps,
this->NumberOfTimeSteps);
```
is supposed to update the set time steps in ParaView from (0, 0.111111 …) to (0, 2.1, 4.2 …) right? But it doesn’t do that.
The
```
int Plugin::RequestData(vtkInformation *vtkNotUsed(request),
vtkInformationVector **vtkNotUsed(inputVector),
vtkInformationVector *outputVector)
// Get the info object
vtkInformation *outInfo = outputVector->GetInformationObject(0);
std::clog << "First time step " <<
outInfo->Get(vtkStreamingDemandDrivenPipeline::TIME_STEPS())[0] << std::endl;
std::clog << "Last time step: " <<
outInfo->Get(vtkStreamingDemandDrivenPipeline::TIME_STEPS())[this->NumberOfTimeSteps-1] << std::endl;
int nSteps = outInfo->Length(vtkStreamingDemandDrivenPipeline::TIME_STEPS());
double* steps = outInfo->Get(vtkStreamingDemandDrivenPipeline::TIME_STEPS());
...
```
“follow” the changes done in **myPlugin:RequestInformation** (I get the expected values), but
```
double requestedTimeValue = outInfo->Get(vtkStreamingDemandDrivenPipeline::UPDATE_TIME_STEP());
```
still follows the default (0, 0.111111, 0,22222, … 1) time step values (done by using the frame command buttons such as “next frame” etc.) and returns those default values.
Do you maybe see what am I missing here?
I followed the suggested **VTK/IO/XML/vtkXMLReader.cxx** (excellent source for learning) and **Plugins/CDIReader/CDIReader\_Plugin.cxx**.
Thank you for your support.
---
### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [February 13, 2020, 9:47am UTC](https://discourse.paraview.org/t/paraview-plugin-setting-multiple-vtkmultiblockdatasets-as-output/3542/4 "2020-02-13T09:47:05Z")
> [@penkod](#):
>
> is supposed to update the set time steps in ParaView from (0, 0.111111 …) to (0, 2.1, 4.2 …)
Yes.
Nothing seems out of place in you code so far.
---
### Author:  [@penkod](https://discourse.paraview.org/u/penkod)
#### Post date: [February 13, 2020, 9:56am UTC](https://discourse.paraview.org/t/paraview-plugin-setting-multiple-vtkmultiblockdatasets-as-output/3542/5 "2020-02-13T09:56:24Z")
Got it working!
In my **myPlugin.xml** file I’ve included
```
Available timestep values.
```
and now under the **Information** tab (next to **Properties** tab) I have all my time indices and time values listed (as a table) + the **frame time values are now correct**!
The
```
double requestedTimeValue = outInfo->Get(vtkStreamingDemandDrivenPipeline::UPDATE_TIME_STEP());
```
, as expected, returns the wanted time values too.
Thank you, Mathieu, for your guidance. 🙂
---
### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [February 13, 2020, 9:57am UTC](https://discourse.paraview.org/t/paraview-plugin-setting-multiple-vtkmultiblockdatasets-as-output/3542/6 "2020-02-13T09:57:17Z")
Nice, I forgot about the XML part.
---
### Author:  [@penkod](https://discourse.paraview.org/u/penkod)
#### Post date: [February 13, 2020, 10:19am UTC](https://discourse.paraview.org/t/paraview-plugin-setting-multiple-vtkmultiblockdatasets-as-output/3542/7 "2020-02-13T10:19:52Z")
Another relevant question.
Is it possible to update the number of time steps and time step values when **myPlugin::RequestData** is executed (e.g. also after pressing the Apply button)? As before that when **myPlugin::RequestInformation** is executed (before pressing Apply button) I don’t really know yet how many time steps will be available (from which data source the plugin should get the data from is specified later with the help of custom plugin GUI).
---
### Author:  [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [February 13, 2020, 10:26am UTC](https://discourse.paraview.org/t/paraview-plugin-setting-multiple-vtkmultiblockdatasets-as-output/3542/8 "2020-02-13T10:26:28Z")
No, this is a design limitation.
You should do all that is required to figure out your temporal information in RequestInformation.
Alternatively, you can use a LiveSource.