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# show array as polygon?

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i''m sitting here and trying to show my array named test[3][3][3] as polygons... i tried this but it doesn''t work
glBegin(GL_POLYGON);
glColor3f(0.0f,1.0f,0.0f);
glVertex3f( test[0][0][0], test[0][0][0], test[0][0][0]);
glVertex3f( test[0][0][1], test[0][1][0], test[1][0][0]);
glVertex3f( test[0][0][2], test[0][2][0], test[2][0][0]);

glEnd();


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glVertex3f(test[0][0][0], test[0][0][1], test[0][0][2]);
glVertex3f(test[0][1][0], test[0][1][1], test[0][1][2]);
glVertex3f(test[0][2][0], test[0][2][1], test[0][2][2]);

maybe...

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nope....

that doesn''t work either

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glBegin(GL_TRIANGLES)

mayby...

LizardCPP

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You must call glBegin(GL_POLYGONS) (plural) not glBegin(GL_POLYGON)

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quote:
Original post by Anonymous Poster
You must call glBegin(GL_POLYGONS) (plural) not glBegin(GL_POLYGON)

no..
quote:

Platform SDK: OpenGL:

...

void glBegin(
GLenum mode
);

...

Parameters
mode

..

GL_POLYGON
Draws a single, convex polygon. Vertices 1 through N define this polygon.

yeah.

you might have culling enabled. try drawing the polygon in different winding. (swap 2 last glvertex calls)

or it simply may not be on screen. This is most likly.

[edited by - RipTorn on December 17, 2003 10:17:35 PM]

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It seems like there is more than one way to display a polygon in a 3x3x3 array, but the way you are doing it will make a triangle with a few of the values from your array as vertex points, as you only have 3 calls to glVertex3f.

The way POLYGON mode works is that you specify the initial vertex, and then a line is drawn to the next vertex specified, and so on until the last vertex is specified, when a line is drawn back to the first vertex. (Note: it doesn''t actually draw these lines, I saw draw as in drawing a mental picture of what the polygon would look like).

If you want more than one polygon, you are going to have to change the code a little to use a for loop perhaps or another GL primitive that I am forgetting about. If you are only interested in making triangles, you can use the TRIANGLES mode to draw a bunch of triangles (where every 3 vertices specifies one triangle).