I was recently asked to review the items that affect render performance in PhotoView 360 for SolidWorks 2011.

Below are a list of factors that affect performance while using PhotoView 360:

1.     Output image size (as it is being created, the output image is stored in uncompressed format before it is converted to the desired output format; this can take a lot of memory; as a general rule the smaller the rendering the faster it will be)

1.1. There is currently a 11580 X 11580 pixel limit to the size of the output file. This is true no matter what kind of hardware is available.

1.1.1.   If the user needs to render images larger than this they need to divide the rendering into smaller parts then merge them together in an image editor.

1.2. When rendering using the PhotoView 360 preview window or the integrated preview, the size of the window greatly affects preview render performance.

1.2.1.   Decreasing the size of the preview window will improve performance as a smaller image renders more quickly.

1.2.2.   The performance of the integrated preview, which renders in the SolidWorks Graphics window, can be improved by decreasing the size of the SolidWorks Graphics window. This can be accomplished by splitting the graphics window, shrinking the entire SolidWorks window or shrinking just the graphics window.

2.     Hardware changes to improve performance.

2.1. The kind of graphix card that you have does not directly affect rendering performance. This is because PhotoView 360 uses software rendering. If you are rendering a larger rendering or rendering a large model that consumes a significant amount of system memory, your rendering will be very slow if the computer has to use system cache as disk space to process the rendering (i.e. you start to run low on system memory). The best thing to do to improve performance while rendering large images or working with large models, with your current system, is to get more RAM.

2.1.1.   In this respect users benefit greatly from having a 64 bit machine because they can have more RAM available.

2.1.2.   On a 32 bit machine, using the 3GB switch will also provide a performance benefit by allowing the user to access up to 4GB of RAM. Note that there are some trade offs with system reliability when using the 3GB switch. It is also important to note that the 3GB switch is not “officially” supported by Microsoft or SolidWorks.

2.1.3.   Though we do not rely on the Graphix Processing Unit (GPU) on your graphix card to process renderings, having a supported graphix card with the correct driver is very important for the overall stability of SolidWorks. Go to: http://www.solidworks.com/pages/services/VideoCardTesting.html  to make sure you have a supported graphix card and the latest driver.

2.2. In selecting other hardware, PhotoView 360 is an application that takes full advantage of multiple processors on your machine. Users with multi core machines see dramatic improvements with rendering performance compared to users with fewer cores.

2.3. The last thing you could then do is to get faster processors in your machine.

2.4. Do note that for Real View in SolidWorks 2011 the power of the graphix card is important (but, again, not for the rendering).

3.     Memory consumption during rendering

3.1. Windows and SolidWorks take about 1.5 GB of RAM right off the bat.

3.2. To free up memory, close all other programs when you are rendering.

3.3. Though you can continue working with any model in SolidWorks when the final rendering is taking place, it is important to note that this consumes system resources which can slow down the final rendering.

3.4. You should also try rendering lightweight.

3.4.1.   Note that to make any changes to the appearances that are applied you need to turn lightweight off (i.e. resolve the affected models). But before you render, setting the model to lightweight will save memory.

3.5. Reduce the level of detail in the model. If there are perforated sheetmetal parts or tread plate or anything that is a standard repeated pattern, these should be replicated (if possible) using appearances and decals as opposed to being modeled as features. Just as a large pattern of features can take a long time to rebuild, a large pattern of features can also take a significant amount of system resources and processing time to render.

3.5.1.   Consider using a decal to mimick the look of repeated patterns. This might even be useful while modeling.

3.5.2.   Consider using the surface finish of the appearance to replicate repeated features.

3.5.2.1.        Some appearances have surface finishes that cut holes in the faces onto which the appearance is applied. Consider using one of our perforated appearances (mesh in plastics or perforated in rubber) to replicate repeated holes on the face. If the appearance has to be metal then you can change the illumination to match the illumination of a metal appearance.

3.5.2.2.        Note SP3 of SolidWorks 2011 introduces the ability to create custom hole meshes. Take a look at Rob Rodriguez’s video related to surface finish for more information: https://forum.solidworks.com/message/216481#216481

3.5.2.3.        Use appearance surface finish to visually represent surface patterns like dimples, tread plate or knurling. Note that PhotoView 360 for SolidWorks 2011 supports bump mapping and now displacement mapping for surface finish. Displacement mapping is an effect where the actual geometric position of points over the textured surface are displaced (as opposed to perturbing the surface normals during illumination calculation as in bump mapping); the following images demonstrate the differences between the two. Note that displacement mapping consumes more memory and takes longer to render than bump mapping.

Figure 1 showing bump mapping for the diamond tread plate surface finish

Figure 2 showing displacement mapping for the diamond tread plate surface finish.

3.6. Scheduling a rendering (i.e. rendering using the SolidWorks Task Scheduler; PhotoView 360 -> Schedule Render…) is not only a great way to have final renderings process when you are not using the computer; scheduling a rendering is also a great way to free up system resources to successfully render larger images or models. The reason for this is that SolidWorks is not required to complete a scheduled static rendering. Only a very lightweight application is run when scheduling a static rendering. For this reason scheduled renderings can be significantly faster. In some cases they are the only way to render very large models that cannot complete when SolidWorks is loaded.

3.6.1.   Note this only applies to static renderings (i.e. still shots). Rendered animations still require SolidWorks to be loaded whether or not they are scheduled using the task scheduler.

4.    PhotoView 360 settings that significantly affect performance. Note that with each of these items you make a trade off between the desired rendering/rendering quality and the rendering performance.

4.1. First it is important to understand the render settings that are used in PhotoView 360. The table below (from the SolidWorks help documentation) shows what items are controlled with the good, better, best and maximum final render settings:

4.1.1.   Using a final render quality setting beyond what is needed will needlessly slow down the rendering. Typically, there is little difference between Best and Maximum. The Maximum setting is most effective when rendering occluded spaces or interior scenes or when more than 8 reflections or refractions are required.

4.2. Increasing the number of reflections and refractions beyond what is required will slow the rendering down.

4.2.1.   If a refractive model is a prominent part of the rendering then you will need to turn up the reflections and refractions (i.e. increase the render quality setting) to make light properly travel through the model (one reflection or refraction per reflective or refractive model face). Too many reflections or refractions and the rendering will needlessly take a long time.

4.3. Using Direct Caustics can have an impact on rendering speed.

4.4. Though it is highly recommended that use a camera for all your renderings, it is important to note that turning on Depth of Field can slow down the rendering.

4.5. Some appearances take longer to render than others.

4.5.1.   Brushed and Satin Finish metals can take a long time to render.

4.5.2.   Transparent glass appearances can also render very slowly.