Page 15/36 GLScene.  Time  Interval  in  milliseconds  triggers  onTimer  event.   This   event  is  independent  of cadencer progress event. Async timer is not recommended to replace the cadencer. It is used to execute actions in fixed longer time intervals rather than take care about rendering the scene. GLStaticImposterBuilder Imposters   are   clever   way  how   to   improve   performance   dramatically.  The   basic   idea behind imposters is that before rendering a set of images looking at an object from all sides is rendered and stored in memory. If the object is to be rendered a sprite (2D image) is drawn instead of the mesh. The most appropriate image has to be selected according to the object’s orientation to the camera. This technique is great for many same objects with high polygon count scattered around the scene. On the other hand it consumes a lot of memory. The task of imposter builder is to generate all the images. You can set the size of the image and number of angles images are to be rendered from. This is done by adding coronas. Each corona has minimum and maximum angles as well as number of images in this range. For example if you make corona ranging from 0º to 15º with 24 images the imposter will cover spherical segments 15º wide and 15º high around ‘equator’ of the object. You must call RequestImposterFor function to generate the coronas. Following section describes five HDS components. Height Data Source components provide data   for   TGLTerrainRenderer.   Terrain   is   used   for   rendering   large   outdoor   sceneries.   HDS components load terrain data from different formats and supply suitable data for terrain renderer. GLBitmapHDS This is the easiest format. Bitmap HDS loads grayscale image and converts the data into height field. The grayscale image must be 16 bit. Most paint programs use 8 bit grayscale palette. Make sure you convert the image to 16 bit otherwise the terrain will look terraced. White parts of the image represent the highest altitude and black parts represent zero altitude. TGLCustomHDS [TODO] GLHeightTileFileHDS The source for height field HDS is .htf file. These files are created in [TODO]. This format is most suitable for really large terrains. Ground texture coordinates together with TileSize property are included in .htf file. TileSize of terrain renderer must be the same as TileSize in .htf file. GLBumpmapHDS [TODO] GLPerlinHDS [TODO] CollisionManager [TODO] GLAnimationControler Animation controller is used together with TGLActor object. Animation controller stores animations that are used by actor. Animations can be loaded from Quake md2 format or from Halflife smd format. Animations are accessed by index or name. They can loop, play once or GLScene beginner's guide, Jan Zizka, 2005