Difference between revisions of "Render Subdiv Settings"
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Revision as of 02:36, 13 June 2018
These are considered advanced settings. Usually you should not need to change them.
Fully adaptive: Fully adaptive causes micropolygons to be more heavily subdivided when the surface is stretched by displacements, but reduces the amount of subdivision where the surface is compressed in screen space due to the angle of view or due to displacements. For stills this is usually a good idea, but it can lead to sudden changes between frames in an animation. Turning this off means that the amount of subdivision is quite regular according to the undisplaced surface, and therefore stable in animations, but doesn't give the best image quality when studying each frame separately. Big displacements will look quite faceted when this is turned off.
Force all edges: Force all edges fixes one of the problems that causes gaps between micropolygons. If two neighbouring micropolygons A and B are subdivided to different levels along a shared edge, this can cause gaps. Force all edges causes the shared edges to be subdivided to the same level. This helps in both animations and stills. However, the default is OFF because this feature slightly increases render time. For animations, though, it's probably worth the cost to remove artefacts. The Animation Check... button (on the render node's Advanced tab) will check this setting and suggest that you turn it ON.
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 reduces render times by a small amount.
Detail jittering: For still images you should keep this turned ON. However, there is an error that cause this to change from one frame to the next in an animation, so you should switch it OFF for animations.
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.
Displacement filter: Allows displacements to blend between levels of detail. The effect also depends on detail blending. We recommend that you keep this value at 1.
Jitter shading points: Jitter shading points chooses a random point on each micropolygon as the point where lighting and shaders are calculated. The results of those calculations are used to colour the whole micropolygon. Jittering provides a more natural image, but because of an error in current versions the jitter is different on each frame so it is a source of unwanted noise in animations. The Animation Check... button (on the render node's Advanced tab) will check this setting and suggest that you turn it OFF.
Stabilise ray detail in motion: 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, stabilise ray detail in motion 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.
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.