I know something about the rendering, so I am curious about PA. Does this game apply some techniques to speed up? such as culling, level of detail, proxy image? Or it just renders all planets and units? The culling is a techniques to reduce the number of objects which are sent to the graphics hardware. For example, if you are look at a planet in close distance. The units on other planets doesn't need to be rendered. Level of detail: When the model is too far from the camera, it can be replaced with fewer faces model or even just a icon. Proxy image: The game can render the planet and its units to a texture, and this texture can be used in the background when the planet is far from the camera. I am not developer, so I don't know how the game works. But I guess none of three techniques is used in PA. For culling, I feel no frame rate difference when I zoom in and zoom out. Usually, the frame rate should decrease when I zoom out. This happens on many FPS games, or even some RTS game such as company of hero. If player is seeing the close range, the frame rate can be higher. For level of detail, I guess that the models of the units are always rendered. When I want to assist a fabricator, I must click the unit. If I click the icon of the fabricator, it will be a miss. So I think this game uses the selection buffer to pick up the units. And the icons are not rendered into the selection buffer. Instead of rendering the icon only, PA uses a slower method to implement it. That is "Always render the units". Even if the icon is larger than the unit, the game is still rendering the unit model. And that's why I must click the fabricator exactly. If you have played the SC:FA, you know the units are not rendered when the camera is very high. Only the icons are shown, and these icons are able to be selected. For proxy image. I can see the command line and estimated building position on the planet which is floating in the background and far from my camera. So I think the while planet is always rendered in every frame, and there is no cache or proxy image to reduce this overhead. If I am wrong, please tell me. I will appreciate.