How to render superimposed planar objects in OpenGL?

Question

I am trying to render geographical data obtained at different time with different sensors. Currently, I manage (through OpenGL and QOpenGL widget) to render a single image (i.e. all vertices have a z=0 coordinates). However, I am wondering how to add new "images" (still with different vertices and texture) which can overlap (in the same plane z=0) the others.

Disable depth testing & render in back-to-front order? – genpfault Feb 01 '16 at 19:25 — genpfault, Feb 01 '16 at 19:25
Does this allow transparence between texture ? – floflo29 Feb 01 '16 at 19:30 — floflo29, Feb 01 '16 at 19:30

score 1 · Accepted Answer · answered Feb 02 '16 at 01:15

1

Sample from each texture in your fragment shader doing whatever composing you need, such as additive, though for geospatial data its probably more complex than that.

If using a library that does all that, then simply disable depth testing, and render each layer, adjusting transparency function between passes.

answered Feb 02 '16 at 01:15

Khlorghaal

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@genpfault, Khlorghaal: It seems to be the best idea – floflo29 Feb 02 '16 at 08:23

How to render superimposed planar objects in OpenGL?

1 Answers1