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# OpenGL Basic Transformation

## 3 posts in this topic

Hello everyone,

I have that triangle and I want to move top vertex, how can I do that?

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open up your favorite 3D modeling software, select it, and move it over.

seriously though, if you only want to move a single vertex, then you need to change it's position before you submit it to the gpu.

Edited by slicer4ever
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IF you're using the old OpenGL, then you're probably using something like this to draw the triangle:

I assume you're using glBegin()/glEnd() pairs, since you don't know how to move a vertex.

glBegin(GL_TRIANGLES);
glVertex3f(-1.0f, -1.0f, 0.0f);
glVertex3f( 1.0f, -1.0f, 0.0f);
glVertex3f( 0.0f,  1.0f, 0.0f); //In this example this is the top vertex
glEnd();


So in this code, the top vertex is the last, so to move it, change the values of the last glVertex3f() call.

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I'm a bit confused, do you want to make the triangle a bit taller, or do you actually want to use OpenGL's transformation functions to "resize" it?

Shogun.

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