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Impact of RAM on 3D Graphics

Depending on what you want to show in the 3D window, your graphics demand can vary greatly. In some cases, you might be using heavily textured models, a high resolution nightlights texture, or a map of the Celestial Sphere. I use all of that stuff, because I want my videos and posters to be as visually appealing as possible.

A few years ago, a very heavy scenario that I was running started to behave badly after I added a 16K Celestial Sphere. The 3D window was blurry, and every few frames, textures would break up or disappear. I expected a slow response since there were so many objects in it. The blurring was not expected. After a little digging, I found that I needed to allocate more RAM for my graphics card. This is done through the property page shown below.

To access this page, right-click the scenario name in your browser, and select Properties. Then, under 3D Graphics, select Global Attributes. The values shown in Image and Terrain Cache are the amount of RAM your PC will use to buffer Graphic and Terrain data, instead of constantly accessing your hard drive. The default value for each is 64 MB. If you are running a very graphics-heavy scenario, this may not be enough. If you see blurry or pixelated graphics, it is definitely not enough. Try changing it to this:

Setting your Image Cache to 1 GB has no downside. Your PC’s performance is not impacted, but it really improves rendering time in STK. To be fair, I have not tried this on systems with less than 8 GB of RAM. But RAM is cheap, and there is no such thing as too much RAM.

You can see the difference that a larger RAM cache makes in the following images. The first image was created with a small cache and the second image was created with a large cache.

Increasing the size of your Image Cache has no downside. Your PC’s performance is not impacted, but it really improves rendering time in STK. To be fair, I have not tried this on systems with less than 8 GB of RAM. But RAM is cheap, and there is no such thing as too much RAM.

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Systems Tool Kit (STK)

Modeling and simulation software for digital mission engineering and systems analysis.