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GeneralRe: convert image to bitmap Pin
Luc Pattyn14-Nov-07 6:17
sitebuilderLuc Pattyn14-Nov-07 6:17 
GeneralRe: convert image to bitmap Pin
Mark Salsbery14-Nov-07 8:06
Mark Salsbery14-Nov-07 8:06 
QuestionHelp :-( - DirectX Initialisation issues Pin
MarkB7778-Nov-07 0:47
MarkB7778-Nov-07 0:47 
AnswerRe: Help :-( - DirectX Initialisation issues Pin
Mark Salsbery8-Nov-07 5:55
Mark Salsbery8-Nov-07 5:55 
GeneralRe: Help :-( - DirectX Initialisation issues Pin
MarkB7778-Nov-07 9:52
MarkB7778-Nov-07 9:52 
GeneralRe: Help :-( - DirectX Initialisation issues Pin
Mark Salsbery8-Nov-07 10:10
Mark Salsbery8-Nov-07 10:10 
QuestionOpenGL picking Pin
belloSoft6-Nov-07 6:47
belloSoft6-Nov-07 6:47 
AnswerRe: OpenGL picking Pin
El Corazon6-Nov-07 7:33
El Corazon6-Nov-07 7:33 
belloSoft wrote:
My problem is: to select a street from that city, I have to ReDraw the scene/the whole city to do the picking and see the detailes of that street.
Does any one know how to do the selection / picking without redrawing every thing ?


There are two ways to do picking, three if you count hybrids, but we'll stick with two. One uses the draw cycle evaluating which pixel you touched and what triangle it belongs to, and what group that triangle lies within, etc. That is hardware based and limited by the options available in hardware. http://web.engr.oregonstate.edu/~mjb/cs553/Handouts/Picking/picking.pdf[^] I assume from your message you are doing this.

The second type is via proximity or at least via spatial zone. There are many algorithms a google on "ray intersection octree" or "ray intersection triangle" will produce many ansers. For instance: http://giig.ugr.es/~rgarcia/Poster.pdf[^] You can also do cheap bounding box tests mathematically for large regions. A quad-tree search within a scene for a "picked" locaton can quickly differenciate what object (or objects) you are looking at, and then you can either do a ray-triangle test to find a specific triangle of that subset, or an OpenGL pick of ONLY those few objects of relative usefullness.

There is also obscuration testing. This is fairly new (last few generations) but certainly no longer leading edge stuff, but it will allow you to quickly reduce the objects being drawn to only those visible using an occlusion query. The more you can do to "cut down" what you draw the faster your draw-time. Why draw it at all if it is off the screen? why draw it if it is entirely hidden by another building? etc. Occlusion Query[^]

_________________________
Asu no koto o ieba, tenjo de nezumi ga warau.
Talk about things of tomorrow and the mice in the ceiling laugh. (Japanese Proverb)

GeneralRe: OpenGL picking Pin
belloSoft7-Nov-07 10:40
belloSoft7-Nov-07 10:40 
GeneralRe: OpenGL picking Pin
Jheriko++17-Nov-07 16:49
Jheriko++17-Nov-07 16:49 
QuestionImage in form of matrix Pin
shemhamforash6-Nov-07 4:00
shemhamforash6-Nov-07 4:00 
AnswerRe: Image in form of matrix Pin
Ju@ncho8-Nov-07 2:52
Ju@ncho8-Nov-07 2:52 
QuestionGetting Image properties Pin
sniper475-Nov-07 23:19
sniper475-Nov-07 23:19 
AnswerRe: Getting Image properties Pin
MikeMarq8-Nov-07 4:44
MikeMarq8-Nov-07 4:44 
AnswerRe: Getting Image properties Pin
Pawel Gielmuda9-Nov-07 2:59
Pawel Gielmuda9-Nov-07 2:59 
GeneralRe: Getting Image properties Pin
sniper4710-Nov-07 8:15
sniper4710-Nov-07 8:15 
GeneralRe: Getting Image properties Pin
Luc Pattyn10-Nov-07 14:50
sitebuilderLuc Pattyn10-Nov-07 14:50 
QuestionDirect 3D retained mode Pin
anjeneya5-Nov-07 18:34
anjeneya5-Nov-07 18:34 
QuestionSimple Texturing Pin
Cyrilix5-Nov-07 15:29
Cyrilix5-Nov-07 15:29 
AnswerRe: Simple Texturing Pin
Cyrilix5-Nov-07 15:52
Cyrilix5-Nov-07 15:52 
QuestionPictureBox Bitmap Manipulation Pin
MikeMarq4-Nov-07 7:03
MikeMarq4-Nov-07 7:03 
AnswerRe: PictureBox Bitmap Manipulation Pin
Luc Pattyn4-Nov-07 8:01
sitebuilderLuc Pattyn4-Nov-07 8:01 
GeneralRe: PictureBox Bitmap Manipulation Pin
MikeMarq4-Nov-07 19:47
MikeMarq4-Nov-07 19:47 
Questionis there size limit for displaying an image? Pin
King Tran3-Nov-07 22:55
King Tran3-Nov-07 22:55 
AnswerRe: is there size limit for displaying an image? Pin
Luc Pattyn4-Nov-07 1:33
sitebuilderLuc Pattyn4-Nov-07 1:33 

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