Animating the sample settings in Cycles

Posted on by Oded Maoz Erell

Software:
Blender 2.79

A quick Cycles rendering tip:

There are situations in which we need to render an animation with changing lighting complexity, and as a result, parts of the animation need more samples than others to be effectively rendered.
For example when the camera starts it’s movement on the outside in an exterior scene, and moves into an interior space like house or a cave, or a vehicle, in many cases, the exterior part of the animation can be rendered with much less samples than the interior part.

In such cases, rendering the whole animation with the higher sample settings will demand unneeded render time in the simpler parts of the animation.

One possible solution would be to simply render the animation in two separated render jobs with different sampling settings, one for the less demanding part and another for the more complex part and than append the two parts in an editing / compositing software. but that requires more work on the shot, more management etc.

A simple solution is to animate the sample settings in Cycles.
Make tests at different times along the animation to determine how many samples are needed at each part, and key-frame the settings accordingly.

AnimateSamples

Align camera to view in Blender

Posted on by Oded Maoz Erell

Software:
Blender 2.79

  1. Create a camera.
  2. Press Ctrl + Alt + 0.

Note:
This command will align the Scene’s Active Camera to the view,
And not the camera that is selected as the Active Object.
To make the selected camera the active camera:
In the 3D View select:
View > Cameras > Set Active Object as Camera

Accurate Object Transform and Parameter editing in Blender

Posted on by Oded Maoz Erell

Software:
Blender 2.79

When transforming objects or mesh components,
> Hold Shift to slow the transform and allow more accuracy that way.

When dragging a parameter numeric field to change its value,
> Hold Shift before to have the value change slowly and allow more accuracy that way.

Quick friendly-topology sphere in Blender and 3ds max

Posted on by Oded Maoz Erell

Software:
Blender 2.79 | 3ds max 2017

Untitled-1.jpg

Blender:
Create Cube
Add ‘Subdivision Surface’ modifier and divide it couple of times
Apply the ‘Subdivision Surface’ modifier
Enter Edit mode and spherify the mesh using ‘To Sphere’ Command (Shift + Alt + S)

3ds max:
Create Cube
Add a TurboSmooth modifier and set wanted iterations
add Spherify modifier
Convert to Editable Poly if needed

Set parameters for multiple objects in Blender

Posted on by Oded Maoz Erell

Software:
Blender 2.79

Method A:

1) Select multiple objects

2) Alt + Click wanted parameter and change it

 

Method B:

1) Select multiple objects

2) Set the wanted parameter

3) right click parameter and choose ‘Copy To Selected’
* Do the same for grouped parameters like vectors using ‘Copy All To Selected’

 

 

Fast editing of multiple instanced (linked) objects in Blender

Posted on by Oded Maoz Erell

Software:
Blender 2.79

Editing the mesh or the shader of an object that’s linked to many other objects appearing in the scene can be slow because software needs to update the appearance of all the other instanced objects.

A simple solution to this is to unlink the object you want to edit, perform the necessary editing, and then relink all the othe objects to the updated one.

It’s best to group the objects beforehand so it will be easy to select them for relinking.

To unlink the object for faster editing:
Select the object, Press U and choose ‘Object & Data’

To link multiple objects to one:
Select all the objects, and click the recently edited one to make sure it’s the active object.
Press Ctrl + L and choose ‘Object Data’.

If you didn’t group all the linked objects for easy selection,
A quick way to select all linked objects is to select one of them and press Shift + L to access the ‘Select Linked’ commands.

Simple re-topology in Blender

Posted on by Oded Maoz Erell

Software:
Blender 2.79

Re-topology workflow in Blender is pretty straight forward and convenient,
Even without using a dedicated addon like ‘Bsurfaces’.

The simplest way to create new geometry over an existing surface is to activate snapping in face mode, and activate the ‘Project individual elements on the surface of other objects’ option.
This let’s you extend geometry, create new elements and transform existing elements while they’re constantly sticking to the surface behind them.
This can also be used with ‘Proportional Editing’ to allow organic tweaking of the new mesh over the surface.

Activating the ‘X Ray’ option in the display properties of the new low poly object helps by displaying the new mesh above the original surface.

Retopo

Another helpful tool in the process is the ‘Shrink Wrap’ modifier,
It can be used “press” mesh parts on to the original surface and than applied to create surface-tight mesh that can serve as the basic mesh for Re-topology or be joined to an existing mesh that was created earlier in the Re-topology process.

Retopo2

 

Non-Color texture data in Cycles render

Posted on by Oded Maoz Erell

Software:
Blender 2.78

When loading texture files into a Cycles Image Texture node, it’s a good idea to take a moment to set the Color Space parameter correctly.
This parameter sets how the color data is intended to be used in the shader, that is, if it will be used as ‘Color’ like a Diffuse texture for example, or as ‘Non-Color Data’ like a Normal map texture example.

NRM_Wrong

NRM_Correct

The reason behind this is that texture data encoded in sRGB color space (JPG, PNG,..) intended to be used as color should be ‘linearized’, that means the gamma correction sRGB files are automatically encoded with should be removed, so the the color data will represent linear color values suitable for the processing of shaders and compositing the final rendered image*,
While texture data intended to be used as data like height or direction or percentage, shouldn’t be linearized, assuming that the colors were saved without adding a gamma corrections to them.

A common example of that is when using a normal map stored in PNG format,
When the Color Space parameter is set to ‘Color’ the resulting bump normal might look wrong, and also display hard edges along UV coordinates seams.
Setting the Color Space to ‘Non-Color Data’ will solve the problem and interpret the bump normals correctly.

> usage of a texture as input for a non-color parameter like displacement will automatically use it as linear color.

> 32 bit float formats like exr are automatically interpreted as linear color by the renderer (the viewport material display will still show a differance so it’s better to set it to ‘Non-Color Data’ anyway).

> It should also be noted that Blender has two parameters controlling the interpretation of an image file one in the Image Texture Node that controls the color usage, one in the Node properties that controls how the file format is interpreted,
And also general color management settings that control the display of colors and saving of image files.

> It should also by noted that I’m still baffled by Blender / Cycles color management.. 🙂

* Linear color is also suitable for post rendering / post production compositing for image development and VFX.