The frequently asked questions lists contain short answers to questions about Hypercosm software that are frequently encountered.
Unlike in the world of film and video where models can be of almost unlimited complexity, creating models for the web and for real-time interactive use involves significant performance and file size considerations and trade offs. This FAQ addresses many of the issues that people typically run into when making the switch to modeling for real-time, web based applications.
Performance Questions
Problem: The animation is slow and choppy.
Solution:
- Reduce the polygon count - Hypercosm applets showing scenes with more than 100,000 polygons may run slowly on some machines. For more information on how to reduce the polygon count, see the article How to Reduce the Polygon Count.
- Reduce the object count - Scenes with more than a few hundred objects may run slowly on some machines. For more information on how to reduce the object count, see the article How to Reduce the Object Count.
Solution: Typically, 3D models have a tendency towards large file sizes. Reality is inherently complex. Hypercosm uses a variety of compression schemes to reduce the size of the applet and textures that are created. However, in some cases the automated compression not enough and you will need to modify your model to acheive a reasonable file size.
- Reduce the texture size - Be conservative with the size, number and resolution of your textures. Watch out for large textures in unexpected places like environment maps or places that are not seen in the model such as inside of interiors. The appropriate size for textures will vary, but textures 100kb and larger are generally considered pretty big. You can reduce all of the textures in a model automatically using the texture controls in Hypercosm Teleporter (if you have the Pro version). You can also use a tool such as Photoshop to manually optimize the texture files after they have been emitted by Hypercosm Teleporter.
- Eliminate any unneccessary or hidden objects - It's often possible to reduce the file size by removing or simplifying objects that make a small contribution to the scene. For more information on how to reduce the number of objects, see the article How to Reduce the Object Count.
- Use primitives in place of meshes - Meshes require a lot of data to describe all of the vertices, edges, and faces that make up all of the tiny polygons that form a mesh. A primitive requires far less. For example, a sphere might only require a center and a radius. So, if you can substitute primitives for meshes, you will lower the file size of the model. Note: This only applies to systems that support primitives such as 3ds Max. SketchUp only supports meshes, so this does not apply to SketchUp models.
Solution: If the applet takes a long time to start, then that is usually because a large amount of geometry must be created. The solution is to try to decrease the amount of geometry and the amount of processing that it takes to create this geometry.
- Use square textures - If your model uses a lot of textures, then it may be slow to start up due to textures. Your computer's graphics card requires that textures be square in order to draw them in the 3D scene. However, most textures are not inherently square, so they need to be resized by the processor before they can be displayed. This takes time. You can remove this extra processing by making your textures square to begin with. If you are using Hyprecosm Teleporter Pro, then there is an option to do this automatically for you. Note that square textures may have the adverse effect of increasing the download time, so may need to find a balance between startup time and file size.
- Eliminate or simplify any unneccessary or hidden objects - It's often possible to reduce the startup time by removing or simplifying objects that make a small contribution to the scene. For more information on how to reduce the number of objects, see the article How to Reduce the Object Count.
- Use meshes in place of primitives - Primitives require the computer's processor to generate the many tiny polgyons that are used to depict their surfaces. You can eliminate this extra processing by collapsing primitives to meshes. Note that this will have the adverse effect of increasing file size so you may need to find a balance between startup time and file size. Note: This only applies to systems that support primitives such as 3ds Max. SketchUp only supports meshes, so this does not apply to SketchUp models.
Problem: The lighting is too dark and some of my lights don't seem to be showing up.
Solution: Don't use more than 8 lights in your scene. Most computer graphics video cards can not handle more than 8 lights and any lights after the first 8 are simply ignored, which causes the scene to appear dark.
Problem: - I need realistic lighting and shadows. Is this possible?
Solution: - For some applications, such as architecture, it is essential for the model to look as realistic as possible. Unfortunately, even modern video cards are incapable of producing photorealistic lighting effects in real-time. However, there is a partial solution to this problem. If your model contains mostly diffuse surfaces, then you can acheive realistic lighting by pre-rendering the lighting in the scene using a program such as 3ds Max and then applying the lighting to the objects using textures. This is called "baking on" the lighting. The main downside to this approach is that it increases the file size since it's necessary to download textures for each of the lit surfaces.