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narfidoo

OpenGL OpenGL question

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narfidoo    122
This may be stupid. I''m new. Say I have an array of vertices and an array of indices for triangles as well as an array of normals. How would I render my object in OpenGL? I have tried glDrawElements but that doesn''t work with the normals. I''m not sure what to do. Oh and I don''t want to draw the triangles seperately, I want them to be smoothly shaded together. Thanks, GG

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zedzeek    528
A-B
|/|
C_D

VECTOR verts[] = { A,B,C,D }
VECTOR norms[] = { A,B,C,D }
GLuint indices[] = { 0,1,2,1,2,3 }; // A B C B C D

glVertexPointer( 3, GL_FLOAT, 0, verts);
glNormalPointer( GL_FLOAT, 0, norms);
glDrawElements( GL_TRIANGLES, 6, GL_UNSIGNED_INT, indices );

will draw the two triangles u will also need to enable the clent states for vertices and normals


http://members.xoom.com/myBollux

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narfidoo    122
Oh, I found out my problem.

My array had normals for each triangle, not each vertex. Any way I can do this?
Otherwise, how can I find the normal for a vertex?

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Foible    122
Just use the same normal for each vertex. You can have different normals for each vertex so things can look rounded with some shading type the way I understand it (like if you have polygons connects you put the same normal for vertexes that touch and it rounds it off...I think ) Anyway just put the same normal for each vertex, I know that works.


-=Foible=-

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