OpenGL - lighting with the Phong reflection model (part 2 of 2)

Code samples derived from work by Joey de Vries, @joeydevries, author of learnopengl.com/
All code samples, unless explicitly stated otherwise, are licensed under the terms of the CC BY-NC 4.0 license as published by Creative Commons, either version 4 of the License, or (at your option) any later version.

[@abhishektyagi4624]

Thank you will.

[@glowiever]

specular strength > 1 means the model is not conserving energy right?

[@miko-puk-puk]

Right, the result light value might be greater than the source light value.

[@Zentennen]

What's the advantage of computing the inverse transpose of the model matrix in the vertex shader as opposed to on the cpu? We could have a uniform normal matrix instead that gets passed in cpu-side.

[@isaiahche1214]

You are right. The inverse and transpose functions can be really costly on the shader-side, but because this is for demonstration purposes, I'm assuming that he just went ahead and did it in the vertex shader.

[@anonymousdog7851]

How does the reflect() formula work?

[@zzador]

4:10 You might have used the wrong function here. I think you wanted to use the "pow(x, y)" function here and not the "exp(x)" function that only takes one argument.
specular = pow(max(dot(R, C), 0), k) * lightColor

[@Byynx]

Can someone explain why specular light usually has "halo" effect. what's the logic?

[@thesituation5315]

Hi. Do you know how to make this work in 2D?

[@MrMariozzz78]

i use opegl in dev c++ gl library i guess it pre 2.0 so it dont use GLSL ...can i use phong light with 2.0 pre.version?

[@MrMariozzz78]

i try this source code with basic light ,my pc gpu go for 100 % usage ,,,,no good programming

[@MrDjRayner]

If anyone is a bit lost, or just stumbled on this video and is not following the video series I'd recommend watching the following video first, /watch?v=nS3qwFOPieg, and then coming back to watch this video.

[@truongvantam4994]

please give me the source code of this video