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OpenGL I'm new to OpenGL

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I'm new to OpenGL in python.

I've manage to draw coordinates and put in a camera but the orientation seems off.

From what I've read it should be:

x +
|
/ - - - y +
/
z +

but it seems like it actually draws as

y +
|
/ - - - x +
/
z +

here's what I've got, maybe I've got it implemented backwards?


def gfxInit():
glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT) #clear the color and depth buffers
glLoadIdentity() #clear current (in this case, modelview) matrix to the identity matrix
gluLookAt(3,3,3, 0,0,0, 0,1,0) # at 3,3,3 looking at origin 0,0,0 with vector pointing up 0,1,0

def gfxShowCoords():
# Cartesian: draw X, Y, Z

glBegin(GL_LINES)

# draw positive X
glColor3f(1,0,0) # red
glVertex3f(0,0,0) # origin
glVertex3f(2,0,0)

# draw positive Y
glColor3f(0,1,0) # green
glVertex3f(0,0,0) # origin
glVertex3f(0,2,0)

# draw positive Z
glColor3f(0,0,1) # blue
glVertex3f(0,0,0) # origin
glVertex3f(0,0,2)

glEnd()




I also want to draw cube "tiles" that are 1 h x 1 w x 1/2 high -- these should be wireframe for now but later I want to make them texture mapped. Better to draw them as lines, quads or another method?

Thanks! Edited by greentiger

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X is right, z is in/out, y is up
Many newer cards don't support quads, so you'll need to use line strips or textures on solid cubes

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X is right, z is in/out, y is up
Many newer cards don't support quads, so you'll need to use line strips or textures on solid cubes


So no GL_QUAD_STRIP?
So how would I draw the above dimenions as a cube with the intention to texture it later?

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Just use triangles. You may be able to make a cube using a triangle strip, but I'm not sure if there's some order that would work.
gltranslatef(positionofcube)
glbegin(gl triangles)
glvertex3f for each point

If you need help with the actual points, I can post a better example, but I'm on my cell right now

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Just use triangles. You may be able to make a cube using a triangle strip, but I'm not sure if there's some order that would work.
gltranslatef(positionofcube)
glbegin(gl triangles)
glvertex3f for each point

If you need help with the actual points, I can post a better example, but I'm on my cell right now


after reading your post and googl'ing it's odd that they would trim some of the basic commands--but i guess it would help trim their bulkiness and i guess since quads are made of two triangles it doesn't matter i suppose. still -- odd ...

thanks for the heads up.

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