GL_TRIANGLES needing resetting as GL_QUADS? Quick question

sg57 · Post by **sg57** » Mon Jul 10, 2006 8:19 am

Seeing as how the GU_TRIANGLE_FAN needs to:

glBegin&#40;GL_TRIANGLE_FAN&#41;;

draw a wal for example

glEnd&#40;&#41;;
glBegin&#40;GL_TRIANGLE_FAN&#41;

draw another wall

glEnd&#40;&#41;;

etc...

Since GL_QAUDS isnt really in the PSPGL, I was wondering if the GL_TRIANGLES needs the same treatment as the fan.

Quick and probablay stupid question, i kno, but Id like an answer :-?[/code]

zilt · Post by **zilt** » Mon Jul 10, 2006 8:25 am

Quick answer - no. Each GL_TRIANGLES element is independent from the previous triangle. However, trying to reuse the same veritces in the following triangle sometimes allows the low level driver/hardware to speed up the triangle rendering by converting the GL_TRIANGLES into a GL_TRIANGLE_STRIP - but is heavily dependent on the hardware and order. Google for it if you want more info.

Insert_witty_name · Post by **Insert_witty_name** » Mon Jul 10, 2006 8:36 am

Do a little research on what each one does. GL_TRIANGLES will create a triangle from each 3 points you give it, so you can wrap them all between a glBegin and glEnd.

See this page for more info on them and other primitives.

http://www.rush3d.com/reference/opengl- ... ter02.html