SlideServe
Télécharger Obtenir Pro
Menu
Accueil Pro
Préférences
ApparenceLight Aide et commentaires
© SlideServe · v2026

Honours Graphics 2008

yon avatar
yon
19 diapositives · 325 Views · Sep 01, 2014

Honours Graphics 2008. Session 7. Today’s focus. Indoor environment rendering BSP and Portal techniques revisited. Indoor / urban rendering. Often makes use of BSP / PVS system Octrees and Portal systems in use as well Portals form a solution for PVS creation. BSP.

Honours Graphics 2008 - slide 1
01 / 19Honours Graphics 2008
1 / 17

Télécharger la présentation

Honours Graphics 2008
Une image / un lien ci-dessous est fourni (tel quel) pour télécharger la présentation

Politique de téléchargement : le contenu du site vous est fourni TEL QUEL pour votre information et votre usage personnel ; il ne peut être vendu, concédé sous licence ni partagé sur d’autres sites sans l’accord de son auteur.Le contenu vous est fourni TEL QUEL, pour votre information et votre usage personnel uniquement. Téléchargez la présentation en cliquant sur ce lien. Lors du téléchargement, si vous ne parvenez pas à télécharger une présentation, l’éditeur a peut-être supprimé le fichier de son serveur.Pendant le téléchargement, si vous ne parvenez pas à obtenir une présentation, le fichier a peut-être été supprimé par l’éditeur.

F I N

Plus de contenu associé

Transcription de la présentation

  1. Honours Graphics 2008 Session 7

  2. Today’s focus • Indoor environment rendering • BSP and Portal techniques revisited

  3. Indoor / urban rendering • Often makes use of BSP / PVS system • Octrees and Portal systems in use as well • Portals form a solution for PVS creation

  4. BSP • Several types of BSP trees: • Node-storing BSP • Leaf-storing BSP • Solid BSP • Each BSP type has specific properties that make it more useful for certain purposes

  5. Node BSP • Original BSP tree as described by Fuchs • Chooses dividing plane from available faces in geometry. Stores dividing face in node, passes along remaining faces as appropriate • Not conducive to tasks such as collision detection as the faces on nodes have no spatial relationship • Traditionally used in software renderers as it generates the least amount of splits

  6. Node BSP, image

  7. Leaf BSP • All geometric data stored in leafs • Nodes store only dividing plane • Leafs represent cells that store all the triangles in a list • Cells are convex and it is possible to find the openings between cells (sometimes called portals) • Useful in hardware rendering and techniques such as collision detection • Portals can be used to compute PVS for BSP

  8. Leaf BSP, image

  9. Solid BSP • Expands leafs of leafy BSP to provide solid information • Effective and elegant for techniques such as collision detection

  10. Solid BSP, image

  11. Solid Leafy BSP • Simply combines leafy and solid BSPs to maintain advantages of both

  12. Solid Leafy BSP, image

  13. Portals • Either placed manually by level-designers, or automatically • Automatic placement not optimal, but useful in many cases – such as automatically creating a PVS (requires portal information) • Uses splitting nodes of BSP to determine portals automatically

  14. Portals for rendering • Many advantages: • Theoretically no overdraw (optimal for software rendering) • Allows effects such as transparency and reflection • Can cater for somewhat dynamic environments • Conceptually easy to understand • But: can have significant computational overhead with arbitrary shaped view frusta with large number of planes. • Not as good for urban scenes in general

  15. Portals for rendering, cont. • Automatic portal creation normally produces a very large set of portals • Thus typically has to rely on manually placed portals by level-designers

  16. BSP, Collision detection

  17. Homework • Write code (pseudo or real) for Line-of-Sight determination • boolean GetLOS(BSP t, point a, point b); • Complete for session 9