I want to use a python script to drive channels in other nodes. I assume this is possible but I can't figure out the syntax.
In it's simplest form here is what I am talking about.
ch(“blend1”) = 0.5
This does not work in python. But that is the intention of what I want my python code to do.
Does anyone have any tips?
Thanks
Found 2527 posts.
Search results Show results as topic list.
Technical Discussion » Python Drive Other Node's Channels?
- Enivob
- 2540 posts
- Offline
Houdini Lounge » Transparency with Opengl renderer
- Enivob
- 2540 posts
- Offline
Wow, can you share any of those shaders or techniques for rendering custom GLSL shaders with the default OpenGL ROP for Apprentice?
Houdini Lounge » Parameter Naming Convention (Can SidexFX Adopt One)?
- Enivob
- 2540 posts
- Offline
Hello All,
After working with Houdini for about a year I have come to the conclusion that SideFx does not have any ‘official’ naming convention in place for the naming of parameters. This would be my wish for Houdini 16.
Consider material parameters. In H14 we have a Mantra shader with an emission intensity parameter called “emit_int”. In H15 we have a principled shader with an emission intensity called “emitint”.
Some times there is an underscore between two words and sometimes not. Sometimes there is camel case or not. Sometimes the parameter is pronounceable in English, sometimes not. Sometimes there is a mix of camel case and underscore such as “diff_colorTexture”. Then there is “dispTexTexuture”
It seems developers can just make up parameter names however they see fit. :?:
IMHO all parameters should be pronounceable in English without any additional explanation in a conversational manner. And by that I ask you to image a scenario where two people are discussing how to change a parameter at the company picnic. Person one says “Lets increase the diffuse intensity by a factor of two”. The second person would be able to derive from that statement that the parameter that person #1 was referring to was indeed “diffuse_intensity”, not “diff_int”.
I know, I know it will upset people if you change those old tried and true names but quite frankly every release of Houdini, even the sub releases within a version, always break something. I'll open up a project I just worked on a day ago and the new version claims some value has changed or is no longer available.
Remember, no shortcuts for words, then you have to explain the shortcut. So yes, sub surface scattering will be named “sub_surface_scattering” not “sss” or “subsrfscat” or anything else. it should be spelled like it is said. Spaces are implied to be underscores.
I say bite the bullet SideFX! Write up a document that proposes a naming convention and stick to it.
After working with Houdini for about a year I have come to the conclusion that SideFx does not have any ‘official’ naming convention in place for the naming of parameters. This would be my wish for Houdini 16.
Consider material parameters. In H14 we have a Mantra shader with an emission intensity parameter called “emit_int”. In H15 we have a principled shader with an emission intensity called “emitint”.
Some times there is an underscore between two words and sometimes not. Sometimes there is camel case or not. Sometimes the parameter is pronounceable in English, sometimes not. Sometimes there is a mix of camel case and underscore such as “diff_colorTexture”. Then there is “dispTexTexuture”
It seems developers can just make up parameter names however they see fit. :?:
IMHO all parameters should be pronounceable in English without any additional explanation in a conversational manner. And by that I ask you to image a scenario where two people are discussing how to change a parameter at the company picnic. Person one says “Lets increase the diffuse intensity by a factor of two”. The second person would be able to derive from that statement that the parameter that person #1 was referring to was indeed “diffuse_intensity”, not “diff_int”.
I know, I know it will upset people if you change those old tried and true names but quite frankly every release of Houdini, even the sub releases within a version, always break something. I'll open up a project I just worked on a day ago and the new version claims some value has changed or is no longer available.
Remember, no shortcuts for words, then you have to explain the shortcut. So yes, sub surface scattering will be named “sub_surface_scattering” not “sss” or “subsrfscat” or anything else. it should be spelled like it is said. Spaces are implied to be underscores.
I say bite the bullet SideFX! Write up a document that proposes a naming convention and stick to it.
Houdini Learning Materials » Fireball Shader
- Enivob
- 2540 posts
- Offline
Not all viewports are created equal. You should list your hardware specs in your signature.
Does it look ok when you render?
Does it look ok when you render?
Houdini Indie and Apprentice » how do you make? simple geometry eg cuboid with attributeVop
- Enivob
- 2540 posts
- Offline
You probably want to use a Wrangle for that.
Checkout Houdini Tricks.
http://houdinitricks.com/post/114520785099/quicktip-cvex-wrangle-vop-nodes [houdinitricks.com]
Checkout Houdini Tricks.
http://houdinitricks.com/post/114520785099/quicktip-cvex-wrangle-vop-nodes [houdinitricks.com]
Technical Discussion » Multiple material slots
- Enivob
- 2540 posts
- Offline
Export from Blender using FBX and you will get a subnet with all your objects as individual objects. The Houdini FBX importer will also create a SHOP net inside the subnet called 'materials". You can then tweak those materials or reassign as you see fit.
Also, with OBJ files you can leverage groups output from Blender inside of Houdini. Just drop down a Material node in the SOP context and you can add many materials each affecting only a single group of faces.
So the solution is proper export from Blender and then fix up inside of Houdini after import.
Also, with OBJ files you can leverage groups output from Blender inside of Houdini. Just drop down a Material node in the SOP context and you can add many materials each affecting only a single group of faces.
So the solution is proper export from Blender and then fix up inside of Houdini after import.
Technical Discussion » for loop boundry
- Enivob
- 2540 posts
- Offline
I kind of feel the same way. I liked the old FOREACH. Jumping inside did not bug me. This new way, while more flexible, does seem a bit more visually sloppy.
Houdini Indie and Apprentice » Point cloud attributes
- Enivob
- 2540 posts
- Offline
You can use vex code in a wrangle to access each point. Typically points will have only the “P” attribute, maybe “v” for velocity if they are moving.
Also, try viewing the Geometry Spread sheet with the node selected. You should be able to see the attributes in spreadsheet form.
Also, try viewing the Geometry Spread sheet with the node selected. You should be able to see the attributes in spreadsheet form.
Houdini Learning Materials » expressionGlobals
- Enivob
- 2540 posts
- Offline
You are running in HScript mode, not Python mode. @1:15, in your video, do you see that “H” as an Icon? Click that “H” and change it to Python. Then try your globals.
Technical Discussion » Houdini15 for MacOS - Crash report
- Enivob
- 2540 posts
- Offline
Did you check the minimum requirements for running Houdini? Many Macs don't actually meet that requirement. List your hardware in your signature.
Technical Discussion » CPU Swap Crashes Houdini 15
- Enivob
- 2540 posts
- Offline
Ah,
I did have a copy of H14.470 installed and tried that as well. Mantra does not crash, however, it does not render either. The console has a more tidy message with the TRACEBACK BEGIN/END.
Here is what is in the crash log.
Crash report from Admin; Houdini FX Version 15.0.277
Uptime 60 seconds
Thu Nov 05 14:34:11 2015
Caught signal 4
Traceback from 4900 ThreadId=0x00000758
+0x0fd30037
I did have a copy of H14.470 installed and tried that as well. Mantra does not crash, however, it does not render either. The console has a more tidy message with the TRACEBACK BEGIN/END.
Here is what is in the crash log.
Crash report from Admin; Houdini FX Version 15.0.277
Uptime 60 seconds
Thu Nov 05 14:34:11 2015
Caught signal 4
Traceback from 4900 ThreadId=0x00000758
+0x0fd30037
Technical Discussion » CPU Swap Crashes Houdini 15
- Enivob
- 2540 posts
- Offline
I am using CPUID and HWMonitor to inspect my hardware. It runs as cool as the last CPU @78F idle and 142F under full 8 core load.
Blender is clearly using all 8 threads when rendering without a problem also Handbrake can encode video using all 8 threads so I am not ready to say the CPU is bad yet. It was purchased new and sealed. I have built many computers over the years so I feel like I did the install correctly with the thermal paste and fan.
Maybe the CPU needs to burn in or something funky like that..?
I managed to get some console feedback. What is odd is I see mention of VRAY in the text. I don't even have VRAY and Apprentice would not run it anyway.
This message appears in the console after I see all 8 buckets appear in the viewport.
Blender is clearly using all 8 threads when rendering without a problem also Handbrake can encode video using all 8 threads so I am not ready to say the CPU is bad yet. It was purchased new and sealed. I have built many computers over the years so I feel like I did the install correctly with the thermal paste and fan.
Maybe the CPU needs to burn in or something funky like that..?
I managed to get some console feedback. What is odd is I see mention of VRAY in the text. I don't even have VRAY and Apprentice would not run it anyway.
This message appears in the console after I see all 8 buckets appear in the viewport.
Technical Discussion » CPU Swap Crashes Houdini 15
- Enivob
- 2540 posts
- Offline
Hi All,
Upgraded my AMD Phenom X6 to a FX8370 today, on an Asrock 970M Pro3 motherboard. This processor is supported by the motherboard and the Windows desktop comes up fine. I am not overclocking anything, just default CPU out of the box.
However, whenever I try to Add a Skylight to an empty default scene Houdini 15.277 crashes. Also if I add a sphere to the scene and add no lights then render with mantra, mantra crashes. This is the same exact hardware only the CPU has been swapped.
All other software, I use, seems to work fine. For instance I can render in Blender without crashes and play games without crashing and use After Effects without crashing.
It seems odd to me that Houdini would be so sensitive to a CPU swap so I thought I would just throw this out to the community and see if anyone has any tips or similar experiences?
Upgraded my AMD Phenom X6 to a FX8370 today, on an Asrock 970M Pro3 motherboard. This processor is supported by the motherboard and the Windows desktop comes up fine. I am not overclocking anything, just default CPU out of the box.
However, whenever I try to Add a Skylight to an empty default scene Houdini 15.277 crashes. Also if I add a sphere to the scene and add no lights then render with mantra, mantra crashes. This is the same exact hardware only the CPU has been swapped.
All other software, I use, seems to work fine. For instance I can render in Blender without crashes and play games without crashing and use After Effects without crashing.
It seems odd to me that Houdini would be so sensitive to a CPU swap so I thought I would just throw this out to the community and see if anyone has any tips or similar experiences?
Technical Discussion » Crowd State Velocity
- Enivob
- 2540 posts
- Offline
In the Crowd Solver, under Animation Behavior, you can increase the overall speed. Double it to 200% if you want a faster animation.
Houdini Indie and Apprentice » 2D plane and alpha channel
- Enivob
- 2540 posts
- Offline
Just add a principled shader to your plane (called a grid in houdini).
Activate the texture map for the diffuse surface and place your diffuse texture there. Do the same thing for opacity only use the alpha version of the texture for that slot.
Activate the texture map for the diffuse surface and place your diffuse texture there. Do the same thing for opacity only use the alpha version of the texture for that slot.
Technical Discussion » Rendering Stops at 2am...hmmm...
- Enivob
- 2540 posts
- Offline
Maybe power saving right?
I had some problems, a while ago, where I could not render through the night. It was a combination of power saving (the hard drive was powered down when idle) and the nVidia driver TDR issue.
My machines are now set to always on and I have altered the registry to disable the TDR “feature”.
It is weird that a computer can consider itself as idle when the CPU is pegged rendering.
I had some problems, a while ago, where I could not render through the night. It was a combination of power saving (the hard drive was powered down when idle) and the nVidia driver TDR issue.
My machines are now set to always on and I have altered the registry to disable the TDR “feature”.
It is weird that a computer can consider itself as idle when the CPU is pegged rendering.
Technical Discussion » no method of pointIntAttribValues for vertex data?
- Enivob
- 2540 posts
- Offline
Houdini Indie and Apprentice » Houdini First Impression
- Enivob
- 2540 posts
- Offline
Mantra is actually pretty vast and has some extreme flexibility with routing data from a scene to various material/shader parameters.
I like the way Houdini handles the background for .EXR output. It is kind of like old school Blender style (pre 2.5).
To see your skymaps in the background and viewport you have to enable that under the Skylight object. I always do this. When I get to After Effects I can choose to Ignore or Use the alpha channel. If I choose to ignore, Houdini has rendered the background into the alpha area and I can use it in my comp. Otherwise I can drop the sky out using one of the other alpha modes. So the background is always there. If you ignore the alpha you can use it.
I like the way Houdini handles the background for .EXR output. It is kind of like old school Blender style (pre 2.5).
To see your skymaps in the background and viewport you have to enable that under the Skylight object. I always do this. When I get to After Effects I can choose to Ignore or Use the alpha channel. If I choose to ignore, Houdini has rendered the background into the alpha area and I can use it in my comp. Otherwise I can drop the sky out using one of the other alpha modes. So the background is always there. If you ignore the alpha you can use it.
Houdini Lounge » Good ressources for crowd and peoples
- Enivob
- 2540 posts
- Offline
There is …
http://3drt.com/store/ [3drt.com]
http://gameartiste.com/store [gameartiste.com]
http://www.blendswap.com/terms/category/characters [blendswap.com]
https://www.cgtrader.com/lowpoly-3d-models/character-people [cgtrader.com]
http://www.daz3d.com/animals-and-creatures [daz3d.com]
More than likely any model you find you will have to do some tweak work on in the form of animating it in it's host package.
http://3drt.com/store/ [3drt.com]
http://gameartiste.com/store [gameartiste.com]
http://www.blendswap.com/terms/category/characters [blendswap.com]
https://www.cgtrader.com/lowpoly-3d-models/character-people [cgtrader.com]
http://www.daz3d.com/animals-and-creatures [daz3d.com]
More than likely any model you find you will have to do some tweak work on in the form of animating it in it's host package.
Houdini Indie and Apprentice » is there way i can Ctrl + C then Ctrl V copy faces
- Enivob
- 2540 posts
- Offline
Just make your selection and then click on the Group tool under the Model tab along the top of the interface. This will create a group node and populate the pattern field with your selection.
If you really need a copy of the original or new group you can split the network as you see fit.
If you really need a copy of the original or new group you can split the network as you see fit.
-
- Quick Links