* basic pbr example

pbr implementation  includes rpbr.h and few shader files header only file, which self contain everything needed for pbr rendering. Few textures and one model of the car which is under free licence which is included inside basic_pbr.c example file  currently supported shader versions are 120 and 330 , version 100 has small issue which I have to resolve

* Unloading PBRMAterial

I forgot unloading PBRMaterial

* fix small issue with texOffset assigment.

value was Vector4 at first but I found out it would be unclear for and users, so I change to have two Vector2 instead, but forgot to assign offset .

* Changed size of textures and file name changed

Changed size of textures from 2048x2048 to 1024x1024 and file name changed to shaders_basic_pbr.c ,
Added the function PBRModel PBRModelLoadFromMesh(Mesh mesh);
but GenMeshPlane(2, 2.0, 3, 3) culdn't be used because it crash once GenMeshTangents() is used with that plane mesh

* Added glsl 100 and 120 shaders to lightmap example.

* Fixed lightmap example resource loading on web.

* add example for deferred rendering/shading

* adapt convention

---------

Co-authored-by: 27justin <me@justin.cx>

* Simplify POI selection

* Improve mouse logic

* Add colour cycles to the shader to show finer details. Works well with high iteration numbers

* Testing things...

* Actually fix zoom. Also allow user to reset camera with 'R'

* Reset max iterations

* Tidying & comments

* Revert to original if statement

* Make mouse logic more readable

* Style conventions

* Coding conventions - f postifx on floating points

* Missed a few f postfixes

* Texture Tiling Example - luis605

* Removed SetTraceLogLevel(LOG_WARNING);

* Add a depth buffer example.

* Fixed a typo

* JSON parser: Use array for function params (#2255)

* Parser: follow C convention of type before name

* Update file names in build scripts

* Rename lighting_instanced shader to instancing

Disable color vertex attribute if not provided by mesh

Simplified example

* Add Conway's Game of Life compute shader example.

* Fix various shaders problems, and tune command buffer size.

* Various coding convention changes.

Removed unneeded resources to use raylib ones.

Simplified some parts and reviewed for a correct computation of matrices, considering stereo render view/projection per eye transformations

shaders_rlgl_mesh_instanced -> shaders_mesh_instancing

Co-authored-by: Jeffery Myers <JefMyers@blizzard.com>

* rlDrawMeshInstanced first attempt

* rlDrawMeshInstanced OpenGL 3.3 and VAO checks

* rlDrawMeshInstanced GetShaderAttribLocation; comments

* example instanced shader

* RLGL_STANDALONE RAYMATH_STANDALONE Vector4

* apply suggested naming changes; add instanced mesh example

* remove orphan variables

NB glsl100 shader needs testing on "bare metal"

Co-authored-by: codifies <nospam@antispam.com>

It seems something is not working properly...

Co-authored-by: codifies <nospam@antispam.com>

head can't think of any improvement I could use on the shaders for
version 120
This has been tested on Linux (Desktop) requires testing on a Rpi

Co-authored-by: codifies <nospam@antispam.com>

Tested on Raspberry Pi... Just note that platform is very limited by GPU...

* Removed Unused Uniforms

uniform vec3 viewUp;
uniform float deltaTime;

* Removed Unused uniforms

uniform vec3 viewUp;
uniform float deltaTime;

* Updated Source

  Added   - #define PLATFORM_DESKTOP line for desktop users.
            This now will correctly find the proper glsl version for the raymarching.fs file.
  Removed - Uniforms --> deltaTime and viewUp. Including the code that was setting them.
            They were never used and they were triggering a log warning.
  Removed - The const from both screenWidth and screenHeight.
            Now they can be used to update the shader resolution when screen is resized.
            NOTE : This is a quick fix and probably not the best idea.
  Added   - IsWindowResized() to check if screen is resized.
            If window is resized then width, height and shader resolution are updated.
  Changed - MIT tag at bottom right color value to BLACK. Now it's easier to see.

* Closer Match to original code

* Removed the PLATFORM_DESKTOP Define