Stencil functionality for rlgl.

[dnxa]

I have already implemented this myself:

#include "rlgl.h"
#include "glfw3.h"

#define GL_ALPHA_TEST	 0x0BC0
#define GL_GREATER   	 0x0204

// Stencil masks
void beginStencil()
{
	rlDrawRenderBatchActive();
	glEnable(GL_STENCIL_TEST);
}

void beginStencilMask()
{
	glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
	glStencilFunc(GL_ALWAYS, 1, 0xFF);
	glStencilOp(GL_KEEP, GL_KEEP, GL_REPLACE);
	glEnable(GL_ALPHA_TEST);
	glAlphaFunc(GL_GREATER, 0.5f);
}

void endStencilMask()
{
	rlDrawRenderBatchActive();	
	glDisable(GL_ALPHA_TEST);	
	glStencilFunc(GL_EQUAL, 1, 0xFF);
	glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP);
	glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
}

void endStencil()
{
	rlDrawRenderBatchActive();
	glDisable(GL_STENCIL_TEST);
}

glfw3.h is from Raylib's 'external\glfw\include\GLFW' directory.

You can then use it like so:

beginStencil();

  beginStencilMask();
  
  // Draw mask
  
  endStencilMask();
  
  // Draw what you want to be masked

endStencil()

It's very useful, flexible, and simple to use for making your game look nice, and I think it should be a part of rlgl.

[Veslo5]

Awesome, did you considered making pull request?

[raysan5]

This is an advance feature that not many users could need in raylib, I prefer not to add it to main library, in any case it can be added as an example.

[Veslo5]

Ok, understandable :)

[bagomot]

I needed it, I’ll have to connect opengl.