Render - Extra Tab
This documentation applies to Terragen 2 and 3. In Terragen 4 these settings have moved to other tabs or other nodes.
- Detail blending: This controls how much blending occurs between levels of detail as the distance between camera and surface changes. Blending also softens the appearance of surfaces. Higher blending values increase render time. For still images we recommend that you set this to 0 for the fastest render times. For animations we recommend values between 0.5 and 1. The Animation Check button (on the render node's Advanced tab) will check this setting and offer to set it to at least 0.5.
- Microvertex jittering: This setting is important to reduce the appearance of straight lines in some displaced surfaces. For still images we recommend you keep this turned ON. For animations, OFF seems to produce a more stable animation, but ON sometimes reduces render times by a small amount.
- Detail jittering: For still images you should keep this turned ON. However, there is a mistake in the renderer that causes this to change from one frame to the next in an animation, so for animations you should switch it OFF. The Animation Check button (on the render node's Advanced tab) will check this setting and offer to turn it OFF.
- Motion-robust subdivision: This feature's purpose is to blend between levels of detail when calculating shadows and reflections. It aims to provide 2 benefits. First, it changes the appearance of shadows crawling across surfaces as the distance from camera changes. The crawling motion is instead replaced by a gradual blend between different shadow positions. (Unfortunately it's impossible to completely stop the shadows from changing shape, because the terrain that casts the shadows needs to change levels of detail as the camera moves.) Second, because the shadow positions are now blended instead of moving from frame to frame, this should prevent popping that occurs when shadow-casting micropolygons change their shape very close to the shadow-receiving point. Unfortunately, this feature produces artefacts of its own: sometimes a kind of cross-hatching pattern is visible. Therefore it may not be suitable for some scenes. It may also change render times.
- Ray trace objects: If this is checked, objects (plants for example) are rendered using raytracing. Generally speaking this leads to a higher quality image which renders more quickly. The disadvantage to using raytracing is that objects will not be rendered with displacement. If an object has displacement mapping in its textures the raytracer will convert this to bump mapping. More info: Ray Trace Objects and Defer Atmosphere/Cloud
Back to: Render
A single object or device in the node network which generates or modifies data and may accept input data or create output data or both, depending on its function. Nodes usually have their own settings which control the data they create or how they modify data passing through them. Nodes are connected together in a network to perform work in a network-based user interface. In Terragen 2 nodes are connected together to describe a scene.
Literally, to change the position of something. In graphics terminology to displace a surface is to modify its geometric (3D) structure using reference data of some kind. For example, a grayscale image might be taken as input, with black areas indicating no displacement of the surface, and white indicating maximum displacement. In Terragen 2 displacement is used to create all terrain by taking heightfield or procedural data as input and using it to displace the normally flat sphere of the planet.