[Bf-python] blender python script error

[Cook, Rich]

Hi, I'm new to this here blender thingie. I was trying some code out to import a few meshes from a science run, and am getting an error I cannot get past. I was going to import the timesteps as separate meshes, then set keyframes on visibility for each mesh at different timesteps in order to "animate" them. Per http://blenderscripting.blogspot.de/2011/07/scripted-keyframing-of-hide-hide-render.html

bpy.ops.anim.change_frame(frame = 5)

Traceback (most recent call last):
File "<blender_console>", line 1, in <module>
File "/Volumes/MacProHD/cook47-stuff/Programs/graphics/Blender/blender.app/Contents/MacOS/2.68/scripts/modules/bpy/ops.py", line 188, in __call__
ret = op_call(self.idname_py(), None, kw)
RuntimeError: Operator bpy.ops.anim.change_frame.poll() Expected an timeline/animation area to be active

I do have a timeline visible in the GUI. I'm not sure what blender is trying to tell me.

I'm probably going to change approaches and just load one mesh at a time, set up the scene, render, and move to the next, etc. However, my technical curiosity has the best of me here. I'd like to understand why I cannot set a timestep here.

Thanks!

--
?Richard Cook
? Lawrence Livermore National Laboratory
Bldg-453 Rm-4024, Mail Stop L-557
7000 East Avenue, Livermore, CA, 94550, USA
? (office) [phone]
? (fax) [phone]
---
Information Management & Graphics Grp., Services & Development Div., Integrated Computing & Communications Dept.
(opinions expressed herein are mine and not those of LLNL)



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[Bassam Kurdali]

Try

bpy.context.scene.frame_set()

Operators rely on context so it can get hard to satisfy them (you could also try making a timeline window visible). You can override context by paying an optional dict to the operator but I've found this tricky to get right in practice.
Oh, and welcome to this blender thing,
Bassam

Hi,I'mnewtothishereblenderthingie.Iwastryingsomecodeouttoimportafewmeshesfromasciencerun,andamgettinganerrorIcannotgetpast.Iwasgoingtoimportthetimestepsasseparatemeshes,thensetkeyframesonvisibilityforeachmeshatdifferenttimestepsinordertoanimatethem.Perhttp://blenderscripting.blogspot.de/2011/07/scripted-keyframing-of-hide-hide-render.htmlIamgettingthefollowingerror:bpy.ops.anim.change_frame(frame=5)Traceback(mostrecentcalllast):Fileblender_console,line1,inmoduleFile/Volumes/MacProHD/cook47-stuff/Programs/graphics/Blender/blender.app/Contents/MacOS/2.68/scripts/modules/bpy/ops.py,line188,in__call__ret=op_call(self.idname_py(),None,kw)RuntimeError:Operatorbpy.ops.anim.change_frame.poll()Expectedantimeline/animationareatobeactiveIdohaveatimelinevisibleintheGUI.I'mnotsurewhatblenderistryingtotellme.I'mprobablygoingtochangeapproachesandjustloadonemeshatatime,setupthescene,render,andmovetothenext,etc.However,mytechnicalcuriosityhasthebestofmehere.I'dliketounderstandwhyIcannotsetatimestephere.Thanks!<spanclass="Apple-style-span"style="border-collapse:separate;-webkit-border-horizontal-spacing:0px;-webkit-border-vertical-spacing:0px;color:rgb(0,0,0);font-family:Monaco;font-size:13px;font

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[Cook, Rich]

Thanks, that's helpful.
I have been having an issue with the documentation. It's very hard to explore. There doesn't appear to be an API reference that actually enumerates and describes all the various functions. For example, http://www.blender.org/documentation/blender_python_api_2_69_1/info_api_reference.html seems like a good introduction, but I am having trouble understanding the relationship and definition of the various concepts, such as contexts, objects, etc.

For example, what is the difference between bpy.context.scene and bpy.data.scenes['Scene'] ?
Are they pointing to the same object? I don't even know where to look for the answer! Do I need to just practice and keep asking for specifics until it all dawns on me, or is there a really good book or reference to all this?

My goal in the end is to do this, all in python:

Set up camera, lights, and a camera path. Import a mesh to view, and animate the scene, swapping out meshes at regular intervals to let the mesh evolve while zooming in, adjusting lights and properties, etc., to capture the best appearance.

Thanks!

On Nov 7, 2013, at 9:01 AM, Bassam Kurdali <bassam at urchn.org<mailto:bassam at urchn.org>> wrote:

Try

bpy.context.scene.frame_set()

Operators rely on context so it can get hard to satisfy them (you could also try making a timeline window visible). You can override context by paying an optional dict to the operator but I've found this tricky to get right in practice.
Oh, and welcome to this blender thing,
Bassam

"Cook, Rich" <cook47 at llnl.gov<mailto:cook47 at llnl.gov>> wrote:

Hi, I'm new to this here blender thingie. I was trying some code out to import a few meshes from a science run, and am getting an error I cannot get past. I was going to import the timesteps as separate meshes, then set keyframes on visibility for each mesh at different timesteps in order to "animate" them. Per http://blenderscripting.blogspot.de/2011/07/scripted-keyframing-of-hide-hide-render.html

bpy.ops.anim.change_frame(frame = 5)

Traceback (most recent call last):
File "<blender_console>", line 1, in <module>
File "/Volumes/MacProHD/cook47-stuff/Programs/graphics/Blender/blender.app/Contents/MacOS/2.68/scripts/modules/bpy/ops.py", line 188, in __call__
ret = op_call(self.idname_py(), None, kw)
RuntimeError: Operator bpy.ops.anim.change_frame.poll() Expected an timeline/animation area to be active

I do have a timeline visible in the GUI. I'm not sure what blender is trying to tell me.

I'm probably going to change approaches and just load one mesh at a time, set up the scene, render, and move to the next, etc. However, my technical curiosity has the best of me here. I'd like to understand why I cannot set a timestep here.

Thanks!

<span class="Apple-style-span" style="border-collapse: separate; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; color: rgb(0, 0, 0); font-family: Monaco; font-size: 13px; font

--
?Richard Cook
? Lawrence Livermore National Laboratory
Bldg-453 Rm-4024, Mail Stop L-557
7000 East Avenue, Livermore, CA, 94550, USA
? (office) [phone]
? (fax) [phone]
---
Information Management & Graphics Grp., Services & Development Div., Integrated Computing & Communications Dept.
(opinions expressed herein are mine and not those of LLNL)



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[Cook, Rich]

Aha, one thing I notice is that the tool tips take you to the documentation for the python equivalent. That's pretty dang cool.

On Nov 7, 2013, at 9:53 AM, "Cook, Rich" <cook47 at llnl.gov<mailto:cook47 at llnl.gov>>
wrote:

Thanks, that's helpful.
I have been having an issue with the documentation. It's very hard to explore. There doesn't appear to be an API reference that actually enumerates and describes all the various functions. For example, http://www.blender.org/documentation/blender_python_api_2_69_1/info_api_reference.html seems like a good introduction, but I am having trouble understanding the relationship and definition of the various concepts, such as contexts, objects, etc.

For example, what is the difference between bpy.context.scene and bpy.data.scenes['Scene'] ?
Are they pointing to the same object? I don't even know where to look for the answer! Do I need to just practice and keep asking for specifics until it all dawns on me, or is there a really good book or reference to all this?

My goal in the end is to do this, all in python:

Set up camera, lights, and a camera path. Import a mesh to view, and animate the scene, swapping out meshes at regular intervals to let the mesh evolve while zooming in, adjusting lights and properties, etc., to capture the best appearance.

Thanks!

On Nov 7, 2013, at 9:01 AM, Bassam Kurdali <bassam at urchn.org<mailto:bassam at urchn.org>> wrote:

Try

bpy.context.scene.frame_set()

Operators rely on context so it can get hard to satisfy them (you could also try making a timeline window visible). You can override context by paying an optional dict to the operator but I've found this tricky to get right in practice.
Oh, and welcome to this blender thing,
Bassam

"Cook, Rich" <cook47 at llnl.gov<mailto:cook47 at llnl.gov>> wrote:

Hi, I'm new to this here blender thingie. I was trying some code out to import a few meshes from a science run, and am getting an error I cannot get past. I was going to import the timesteps as separate meshes, then set keyframes on visibility for each mesh at different timesteps in order to "animate" them. Per http://blenderscripting.blogspot.de/2011/07/scripted-keyframing-of-hide-hide-render.html

bpy.ops.anim.change_frame(frame = 5)

Traceback (most recent call last):
File "<blender_console>", line 1, in <module>
File "/Volumes/MacProHD/cook47-stuff/Programs/graphics/Blender/blender.app/Contents/MacOS/2.68/scripts/modules/bpy/ops.py", line 188, in __call__
ret = op_call(self.idname_py(), None, kw)
RuntimeError: Operator bpy.ops.anim.change_frame.poll() Expected an timeline/animation area to be active

I do have a timeline visible in the GUI. I'm not sure what blender is trying to tell me.

I'm probably going to change approaches and just load one mesh at a time, set up the scene, render, and move to the next, etc. However, my technical curiosity has the best of me here. I'd like to understand why I cannot set a timestep here.

Thanks!

<span class="Apple-style-span" style="border-collapse: separate; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; color: rgb(0, 0, 0); font-family: Monaco; font-size: 13px; font

--
?Richard Cook
? Lawrence Livermore National Laboratory
Bldg-453 Rm-4024, Mail Stop L-557
7000 East Avenue, Livermore, CA, 94550, USA
? (office) [phone]
? (fax) [phone]
---
Information Management & Graphics Grp., Services & Development Div., Integrated Computing & Communications Dept.
(opinions expressed herein are mine and not those of LLNL)




--
?Richard Cook
? Lawrence Livermore National Laboratory
Bldg-453 Rm-4024, Mail Stop L-557
7000 East Avenue, Livermore, CA, 94550, USA
? (office) [phone]
? (fax) [phone]
---
Information Management & Graphics Grp., Services & Development Div., Integrated Computing & Communications Dept.
(opinions expressed herein are mine and not those of LLNL)



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[Brecht Van Lommel]

For the specific question you are asking, this is probably the page to read:
http://www.blender.org/documentation/blender_python_api_2_69_1/info_quickstart.html

bpy.context.scene is the active scene, while bpy.data.scenes['Scene']
is the scene named 'Scene'. They can be the same, it depends which
scene the user has selected.

Post by Cook, Rich
Thanks, that's helpful.
I have been having an issue with the documentation. It's very hard to
explore. There doesn't appear to be an API reference that actually
enumerates and describes all the various functions. For example,
http://www.blender.org/documentation/blender_python_api_2_69_1/info_api_reference.html
seems like a good introduction, but I am having trouble understanding the
relationship and definition of the various concepts, such as contexts,
objects, etc.
For example, what is the difference between bpy.context.scene and
bpy.data.scenes['Scene'] ?
Are they pointing to the same object? I don't even know where to look for
the answer! Do I need to just practice and keep asking for specifics until
it all dawns on me, or is there a really good book or reference to all this?
Set up camera, lights, and a camera path. Import a mesh to view, and
animate the scene, swapping out meshes at regular intervals to let the mesh
evolve while zooming in, adjusting lights and properties, etc., to capture
the best appearance.
Thanks!
Try
bpy.context.scene.frame_set()
Operators rely on context so it can get hard to satisfy them (you could also
try making a timeline window visible). You can override context by paying an
optional dict to the operator but I've found this tricky to get right in
practice.
Oh, and welcome to this blender thing,
Bassam
Hi, I'm new to this here blender thingie. I was trying some code out to
import a few meshes from a science run, and am getting an error I cannot get
past. I was going to import the timesteps as separate meshes, then set
keyframes on visibility for each mesh at different timesteps in order to
"animate" them. Per
http://blenderscripting.blogspot.de/2011/07/scripted-keyframing-of-hide-hide-render.html

bpy.ops.anim.change_frame(frame = 5)

File "<blender_console>", line 1, in <module>
File
"/Volumes/MacProHD/cook47-stuff/Programs/graphics/Blender/blender.app/Contents/MacOS/2.68/scripts/modules/bpy/ops.py",
line 188, in __call__
ret = op_call(self.idname_py(), None, kw)
RuntimeError: Operator bpy.ops.anim.change_frame.poll() Expected an
timeline/animation area to be active
I do have a timeline visible in the GUI. I'm not sure what blender is trying to tell me.
I'm probably going to change approaches and just load one mesh at a time,
set up the scene, render, and move to the next, etc. However, my technical
curiosity has the best of me here. I'd like to understand why I cannot set
a timestep here.
Thanks!
<span class="Apple-style-span" style="border-collapse: separate;
0px; color: rgb(0, 0, 0); font-family: Monaco; font-size: 13px; font
--
?Richard Cook
? Lawrence Livermore National Laboratory
Bldg-453 Rm-4024, Mail Stop L-557
7000 East Avenue, Livermore, CA, 94550, USA
? (office) [phone]
? (fax) [phone]
---
Information Management & Graphics Grp., Services & Development Div.,
Integrated Computing & Communications Dept.
(opinions expressed herein are mine and not those of LLNL)
_______________________________________________
Bf-python mailing list
Bf-python at blender.org
http://lists.blender.org/mailman/listinfo/bf-python

[Bassam Kurdali]

Some helpful hints that I found useful when learning the api, first few
are from context menu on buttons:
1- right click on a button -> copy data path; gives you the path of the
property based from the datablock it is on, in the copy/paste buffer.
2- right click on a button -> edit source! crib code from blender's UI
itself. (opens in a text editor, you have to browse it to find the file)
3- autocompletion in the py console in blender FTW; lets you explore
almost anything.
4- help - > py api reference; while everything is not perfectly
documented, it is mostly the case, and searchable.
5- outliner-> Datablocks: allows you to brows the data structure in
blender almost exactly as it is in the api.
6- knowing blender helps as you are already familiar with the concepts,
the py api mostly exposes the same stuff you are used to dealing with.

Finally context is a bit of a tricky thing, it passes the same types of
data you get from bpy.data, but this is telling you 'what is my current
state' rather than everything in the file; it is used by operators,
panels, and maybe your own functions. Most easily understood in terms of
tools i.e. : User makes a selection in a viewport(changes context),
Operator runs(for instance, deletes the selection) using that
context,User gets desired result(those vertices are deleted)

From Python they are cumbersome, I tend to avoid them if I can, or use

them sparingly.
Hope that helped!

http://www.blender.org/documentation/blender_python_api_2_69_1/info_quickstart.html
bpy.context.scene is the active scene, while bpy.data.scenes['Scene']
is the scene named 'Scene'. They can be the same, it depends which
scene the user has selected.

Post by Cook, Rich
Thanks, that's helpful.
I have been having an issue with the documentation. It's very hard to
explore. There doesn't appear to be an API reference that actually
enumerates and describes all the various functions. For example,
http://www.blender.org/documentation/blender_python_api_2_69_1/info_api_reference.html
seems like a good introduction, but I am having trouble understanding the
relationship and definition of the various concepts, such as contexts,
objects, etc.
For example, what is the difference between bpy.context.scene and
bpy.data.scenes['Scene'] ?
Are they pointing to the same object? I don't even know where to look for
the answer! Do I need to just practice and keep asking for specifics until
it all dawns on me, or is there a really good book or reference to all this?
Set up camera, lights, and a camera path. Import a mesh to view, and
animate the scene, swapping out meshes at regular intervals to let the mesh
evolve while zooming in, adjusting lights and properties, etc., to capture
the best appearance.
Thanks!
Try
bpy.context.scene.frame_set()
Operators rely on context so it can get hard to satisfy them (you could also
try making a timeline window visible). You can override context by paying an
optional dict to the operator but I've found this tricky to get right in
practice.
Oh, and welcome to this blender thing,
Bassam
Hi, I'm new to this here blender thingie. I was trying some code out to
import a few meshes from a science run, and am getting an error I cannot get
past. I was going to import the timesteps as separate meshes, then set
keyframes on visibility for each mesh at different timesteps in order to
"animate" them. Per
http://blenderscripting.blogspot.de/2011/07/scripted-keyframing-of-hide-hide-render.html

bpy.ops.anim.change_frame(frame = 5)

File "<blender_console>", line 1, in <module>
File
"/Volumes/MacProHD/cook47-stuff/Programs/graphics/Blender/blender.app/Contents/MacOS/2.68/scripts/modules/bpy/ops.py",
line 188, in __call__
ret = op_call(self.idname_py(), None, kw)
RuntimeError: Operator bpy.ops.anim.change_frame.poll() Expected an
timeline/animation area to be active
I do have a timeline visible in the GUI. I'm not sure what blender is
trying to tell me.
I'm probably going to change approaches and just load one mesh at a time,
set up the scene, render, and move to the next, etc. However, my technical
curiosity has the best of me here. I'd like to understand why I cannot set
a timestep here.
Thanks!
<span class="Apple-style-span" style="border-collapse: separate;
0px; color: rgb(0, 0, 0); font-family: Monaco; font-size: 13px; font
--
?Richard Cook
? Lawrence Livermore National Laboratory
Bldg-453 Rm-4024, Mail Stop L-557
7000 East Avenue, Livermore, CA, 94550, USA
? (office) [phone]
? (fax) [phone]
---
Information Management & Graphics Grp., Services & Development Div.,
Integrated Computing & Communications Dept.
(opinions expressed herein are mine and not those of LLNL)
_______________________________________________
Bf-python mailing list
Bf-python at blender.org
http://lists.blender.org/mailman/listinfo/bf-python

_______________________________________________
Bf-python mailing list
Bf-python at blender.org
http://lists.blender.org/mailman/listinfo/bf-python