WebGL - Orthographic 3D

11:40 AM

Yesterday, we have dived into the visual world of WebGL, and completed the initial setup, and drew a simple 2D "F" figure. Today, I tried creating some 3D magic using WebGL. It was quite similar to 2D. Just needed to add another dimension to the translation and scale matrix. 

Rotation was a different thing. Since in 2D, we can have rotation about only one, namely Z-axis. But in 3D, rotations about 3 different axes are possible. Hence we need to create 3 different methods for rotation about X, Y and Z axes.

WebGL draws shapes using primitive triangles. We provide it with vertexes of triangles, and it draws them. For example, if we want to draw a rectangle, we would provide it with 2 sets of 3 vertex. One set of 3 vertex draws one triangle, and another draws another. If we provide the vertex such that the triangles have a common hypotenous, we get a rectangle.

For the 3D F, I needed 16 rectangles. Hence I needed to supply 16 * 6, 96 vertices. Following is what I achieved today, the controls are similar to previous post.


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