Re: GL_LINES vs GL_QUADS with glPolygonMode GL_LINE
Michael I Gold <[email protected]> Tue, 05 Jun 2007 23:00:23 -0800
| Newsgroups | gmane.games.devel.opengl |
|---|---|
| Organization | Fat City Network Services, San Diego, California |
| Message-ID | <[email protected]> |
If you render two quads which share an edge (e.g. in a quad strip, all adjacent quads share an edge), those edge lines will be drawn twice. In addition, PolygonMode(LINE) requires additional primitive setup (e.g. face selection) which lines do not require. Whether the latter actually impacts performance depends on the implementation. Roland Krause wrote: Yet another likely dumb question. Please forgive my ignorance but I was wondering: I have to draw a mesh consisting of lots and lots of quads. Is there a performance difference between drawing the lines of this mesh using GL_LINES or GL_LINE_LOOP versus calling GL_QUADS with a glPolygonMode of glPolygonMode(GL_FRONT, GL_LINE) and culling the backside? Note that I am using glDisplayLists in any case to execute the final result. I know the amount of data sent to the card is slightly different but does that matter? Best regards and thanks for your insightful comments Roland ----- FAQ and OpenGL Resources at: http://www.geocities.com/SiliconValley/Hills/9956/OpenGL ----- FAQ and OpenGL Resources at: http://www.geocities.com/SiliconValley/Hills/9956/OpenGL -- Author: Michael I Gold INET: [email protected] Fat City Hosting, San Diego, California -- http://www.fatcity.com --------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [email protected] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB OPENGL-GAMEDEV-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).