GLSL 4.2 - how to retrieve size of image?

Question

In GLSL 4.2 one can use the image2D datatype with imageLoad and imageStore functions. those functions take ivec to determine which pixel to write/read. in order to calculate the proper ivec, i need to know the size of the image. But how do I retrieve this?

textureSize() seems to work only with samplers, not with images.

How to do it?

What do you mean - not with images? How do you specify "image" in GLSL? — Mārtiņš Možeiko, Mar 19 '12 at 14:09
@MārtiņšMožeiko I think he's made it pretty clear, look into the [shader_image_load_store extension](http://www.opengl.org/registry/specs/ARB/shader_image_load_store.txt) for more information. — Christian Rau, Mar 19 '12 at 14:12

score 2 · Answer 1 · edited Jun 02 '14 at 13:55

2

You can use imageSize() in GLSL 4.3. Take a look at GLSL specification from OpenGL.org.

edited Jun 02 '14 at 13:55

jozxyqk

16,424
12
91
180

answered Nov 06 '12 at 21:08

nebo3d

51
2

no idea why this was downvoted. spot on answer after the function was added – jozxyqk Jun 02 '14 at 13:55

score 1 · Accepted Answer · answered Mar 19 '12 at 22:21

1

You don't. They didn't put in a function to get the image's size, so you'll have to pass it in via a uniform.

answered Mar 19 '12 at 22:21

Nicol Bolas

449,505
63
781
982

GLSL 4.2 - how to retrieve size of image?

2 Answers2