Z-Buffering in the 3D World
Z-buffering is a computationally intensive process of determining which polygons are behind which (from the active viewpoint), so that a scene is drawn correctly with the proper depth.
When you render a scene from your 3D Application, visible portions of objects with correct mapping, shadows, and so on are produced for a near-photorealistic reproduction of the way the physical world is perceived.
This process can be much too slow for real-time games, but most game engines have the capability to perform modified z-buffering (a faster but less accurate process than in your 3D Application).
For fastest performance, however, binary separation planes (or BSPs) are created to give the processor a simple decision process as to what gets drawn in front of what.
These planes divide concave (self-overdrawing) objects into convex pieces.
These pieces, combined with the transform of the object, can be quickly evaluated by the computer to determine proper placement of objects.
Most real-time games also have a far clipping plane-a predetermined distance from the user's viewpoint, beyond which no objects are rendered, even though they are stored in memory.
The far clipping plane allows the designer to greatly increase the number of objects in a game world, because the computer doesn't always have to draw everything simultaneously.
Often, far clipping planes are disguised by fog, so objects do not just "pop" into the universe but appear to arrive out of a misty veil.
Levels of detail (LODs) also are critical in achieving the speed necessary to create an enjoyable game.
In short, they are "stand-in" objects used to represent the real object at a greater distance from the user's viewpoint.
the object is close to the player, the highest-resolution model available is drawn.
When the object takes up a small portion of the screen, a lower polygon count model is swapped in.
Very often, at the greatest distances when the object can still be seen, a colored box is used to represent the object.
The increase in speed is dramatic, because the processor does not have to calculate all the faces of the full object, but it still draws the same number of pixels the object takes up onscreen.
Complex objects (such as trees), which require a large number of polygons even to approximate, can be represented by an x-shaped arrangement of quads.
This arrangement can be mapped with a picture of a high-resolution object and an opacity map (or "cookie cutter" map) that makes everything outside the desired object invisible.
This technique can also be used effectively with LODs or complex game sprites (2D animated objects).
In your 3D Application R2, you can use the LOD manager to effectively switch between different levels of detail based on the object's distance from the camera.
When you render a scene from your 3D Application, visible portions of objects with correct mapping, shadows, and so on are produced for a near-photorealistic reproduction of the way the physical world is perceived.
This process can be much too slow for real-time games, but most game engines have the capability to perform modified z-buffering (a faster but less accurate process than in your 3D Application).
For fastest performance, however, binary separation planes (or BSPs) are created to give the processor a simple decision process as to what gets drawn in front of what.
These planes divide concave (self-overdrawing) objects into convex pieces.
These pieces, combined with the transform of the object, can be quickly evaluated by the computer to determine proper placement of objects.
Most real-time games also have a far clipping plane-a predetermined distance from the user's viewpoint, beyond which no objects are rendered, even though they are stored in memory.
The far clipping plane allows the designer to greatly increase the number of objects in a game world, because the computer doesn't always have to draw everything simultaneously.
Often, far clipping planes are disguised by fog, so objects do not just "pop" into the universe but appear to arrive out of a misty veil.
Levels of detail (LODs) also are critical in achieving the speed necessary to create an enjoyable game.
In short, they are "stand-in" objects used to represent the real object at a greater distance from the user's viewpoint.
the object is close to the player, the highest-resolution model available is drawn.
When the object takes up a small portion of the screen, a lower polygon count model is swapped in.
Very often, at the greatest distances when the object can still be seen, a colored box is used to represent the object.
The increase in speed is dramatic, because the processor does not have to calculate all the faces of the full object, but it still draws the same number of pixels the object takes up onscreen.
Complex objects (such as trees), which require a large number of polygons even to approximate, can be represented by an x-shaped arrangement of quads.
This arrangement can be mapped with a picture of a high-resolution object and an opacity map (or "cookie cutter" map) that makes everything outside the desired object invisible.
This technique can also be used effectively with LODs or complex game sprites (2D animated objects).
In your 3D Application R2, you can use the LOD manager to effectively switch between different levels of detail based on the object's distance from the camera.