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Vray System

In this section you can adjust a variety of VRAYforC4D parameters related to the overall operation of the renderer.

Raycast accelarator

Here you can control various parameters of VRAYforC4D's Binary Space Partitioning (BSP) tree.

One of the basic operations that VRAYforC4D must perform is raycasting - determining if a given ray intersects any geometry in the scene, and if so - identifying that geometry. The simplest way to implement this would be to test the ray against every single render primitive (triangle) in the scene. Obviously, in scenes with thousands or millions of triangles this is going to be very slow. To speed this process, VRAYforC4D organizes the scene geometry into a special data structure, called a binary space partitioning (BSP) tree.

The BSP tree is a hierarchical data structure, built by subdividing the scene in two parts, then looking at each of those two parts and subdividing them in turn, if necessary and so on. Those "parts" are called nodes of the tree. At the top of the hierarchy is the root node - which represents the bounding box of the whole scene; at the bottom of the hierarchy are the leaf nodes - they contain references to actual triangles from the scene.

Max tree depth - the maximum depth of the tree. Larger values will cause VRAYforC4D to take more memory, but the rendering will be faster - up to some critical point. Values beyond that critical point (which is different for every scene) will start to slow things down. Smaller values for this parameter will cause the BSP tree to take less memory, but rendering will be slower.
Min leaf size - the minimum size of a leaf node. Normally this is set to 0.0, which means that VRAYforC4D will subdivide the scene geometry regardless of the scene size. By setting this to a different value, you can make VRAYforC4D to quit subdividing, if the size of a node is below a given value.
Face level coefficient - controls the maximum amount of triangles in a leaf node. If this value is lower, rendering will be faster, but the BSP tree will take more memory - up to some critical point (which is different for every scene). Values below that critical point will make the rendering slower.
Dynamic memory limit (in MB) - the total RAM limit for the dynamic raycasters. Note that the memory pool is shared between the different rendering threads. Therefore, if geometry needs to be unloaded and loaded too often, the threads must wait for each other and the rendering performance will suffer.

Region sequence

Here you can control various parameters of VRAYforC4D's rendering regions (buckets). The bucket is an essential part of the distributed rendering system of VRAYforC4D. A bucket is a rectangular part of the currently rendered frame that is rendered independently from other buckets. Buckets can be sent to idle LAN machines for processing and/or can be distributed between several CPUs. Because a bucket can be processed only by a single processor the division of the frame in too small a number of buckets can prevent the optimal utilization of computational resources (some CPUs stay idle all the time). However the division of the frame in too many buckets can slow down the rendering because there is a some time overhead related with each bucket (bucket setup, LAN transfer, etc).

PictureView Bucket X size - determines the maximum region width in pixels (Region W/H is selected) or the number of regions in the horizontal direction (when Region Count is selected) in Picture View Window.
PictureView Bucket Y size - determines the maximum region height in pixels (Region W/H is selected) or the number of regions in the vertical direction (when Region Count is selected) in Picture View Window.
Viewport Bucket X size - determines the maximum region width in pixels (Region W/H is selected) or the number of regions in the horizontal direction (when Region Count is selected) in Viewport rendering.
Viewport Bucket Y size - determines the maximum region height in pixels (Region W/H is selected) or the number of regions in the vertical direction (when Region Count is selected) in Viewport rendering.
Bucket type - methods of bucket distribution during rendering.
Region sequence type - determines the order in which the regions are rendered. Note that the default Triangulation sequence is best if you use a lot of dynamic geometry, since it walks through the image in a very consistent manner so that geometry that was generated for previous buckets can be used for the next buckets. The other sequences tend to jump from one end of the image to another which is not good with dynamic geometry.
Reverse sequence - reverses the region sequence order, performance will suffer.

Split / Region

Allows to automaticly render a still image across a cinema4d NET renderfarm. Set the number of splits to the number of machines in the network. Set the same number of frames in the cinema4d animation (output c4d preferences) starting with frame1. so when you have 4 machines to render, set the splitting to 4 and the animation to frame 1-4. Render the file on NET and you get 4 images that you can merge easily in Adobe Photoshop or similar applications.

Rendering Split On/Off - lets you turn on or off the render splitting( good for workflow when you have setup a splitting, but want to prerender locally only).
Horizontal Split - split image horizontaly.
Splits number - determinates the number of splits. Set this to the same number of machines on the net (7 PCS = 7 Splits)
Pixel Overlapp this lets you set an overlap of the splitting, always use an overlap greater than 0 as the AA will otherwise have a visible border when merging the final image. You can manually adjust this. We recommend 4-20pixels depending on image size and AA settings.

The image splitting is a very fast and efficient method to render high resolution images across a c4d NET Render network. It is the preferred method for many professionals as it is very stable and more efficient as DR.

Pixel Overlap - lets you manually adjust the pixeloverlaping.
Region ON/OFF - lets you activate full size region render.
Left - pixels from left start.
Top - pixels from top start.
Right - pixels from right start.
Bottom - pixels from bottom start.
Get Last Region Render - this is a method if you don’t want to set the render region by exact pixels but directly in camera editor view. Activate render region tool in c4d, set a region, start to render the region ( you don’t have to wait to finish it) and go to vray system options and press the “get last region render”, vray will then set the pixels in relation to the final output size automaticly for you.

When you render in picture viewer the exact region you have chosen gets rendered only. This is a great time saver and usable for high resolution detail previews or for rerendering only parts of the image ( if there was a mistake p.e.)

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