Rendering in SketchUp

How Rendering 
Works
CHaPteR
4

---

36
Part 1: Overview and Concepts
Fig. 4.1: 
The bottom-left corner of the Shaderlight preview screen indicates rendering progress.
Stage 2: Ray tracing
Ray tracing refers to the action the IRP takes when calculating how light interacts with the 
model’s textured surfaces. At this stage the preview window displays a slowly coalescing image 
(Fig. 4.2). The IRP will indicate the rendering progress in terms of percentage completed. 
Ray tracing speed is affected by the quality and output resolution set for the render and the 
size and detail of the model. 
Stage 3: anti-aliasing
Anti-aliasing is the process during which the render engine smoothes the image’s jagged edges 
and lines, helping to soften and refine the image. The anti-aliasing speed varies, depending on 
the quality and output resolution. Higher quality settings can take a considerable amount of 
time to complete. Lower settings, common for draft quality, tend to limit or not employ any 
anti-aliasing, allowing for faster render times (Fig. 4.3). 

---

37
Chapter 4: How Rendering Works
Fig. 4.2: 
The Shaderlight preview screen displays the image coalescing during the Ray Tracing stage. 
Fig. 4.3: 
The final rendered image is completed.
Computer Hardware and Rendering
The IRP render engines use complex mathematical algorithms to simulate light (ray tracing) and 
generate an image, which requires a considerable amount of computer resources to accomplish. 
The type of computer hardware utilized directly affects the speed of the rendering. 

---