C / C++ / MFC

jeron1 wrote:

because there are 4294967295 entries in each dimension

Member 14812342 wrote:

What does my question has to deal with facebook and drinking behaviour?

glEnable(GL_STENCIL_TEST);  // ENABLE the stencil buffer
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT); // CLEAR the stencil buffer along with colour and depth

window = glutCreateWindow("OpenGL - Base "); // Create window with the given title
// single for now
glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH | GLUT_STENCIL);

      //
			glClear(
			GL_STENCIL_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT);

			glDisable( GL_STENCIL_TEST);
			glEnable(GL_STENCIL_TEST);
			// clear all three buffers
			glClearStencil(0x0);
			glClear(
			GL_STENCIL_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT);
			glStencilMask(GL_TRUE); // MUST enable writing to stencil buffer (??)
			// turn off writing to color buffer
			glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
			// enable only to verify the stencil
			//glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
			// setup stencil function
			// function  - test always are ref and mask bogus , ignored ?
			// referrence
			// mask
			glStencilFunc(GL_ALWAYS, 1, 1);							

			// setup stencil operation
			//glStencilOp(GL_REPLACE, GL_REPLACE, GL_KEEP);			// ??
			// blank here

			//glStencilOp(GL_KEEP, GL_KEEP, GL_REPLACE);
			// get stencil
			// TODO need parameter here to verify 
			parameter_stencil = 42;
			parameter_stencil = Stencil(parameter_stencil);		// parameter);
			glFlush();
			// blank here
			// switch keep area
			if (parameter_stencil == 0) {
				printf(
						"\nStencil full circle parameter %i @function %s @line %i",
						parameter_stencil, __FUNCTION__, __LINE__);
				glStencilFunc(GL_EQUAL, 1, 1);
			}	// keep inside circle
			else {
				printf(
						"\nStencil last circle parameter %i @function %s @line %i",
						parameter_stencil, __FUNCTION__, __LINE__);
				glStencilFunc(GL_NOTEQUAL, 1, 1);
			}	// keep all outside of stencil
		


			{
				// apply stencil 
				//int OpenGL_Render_RealAxis(int parameter = 0)
				//OpenGL_Render_RealAxis(); // int parameter = 0)
				OpenGL_Render_Plus_IMG_Axis(); //int parameter = 0)
				//OpenGL_Render_Minus_IMG_Axis(5); //passed temporary last circle as parameter = 0)
			}

from here I am not sure how to display only the rendered fragment 
I get both stencil and fragment ONLY when writing to color buffer is enabled 

			glStencilMask(GL_FALSE);
			glClear(
						GL_STENCIL_BUFFER_BIT );
			//glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP);
			//glStencilOp(GL_ZERO, GL_ZERO, GL_REPLACE);
			//GL_ZERO
			//Reenable color
			glColorMask( GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
			glClear(
									GL_STENCIL_BUFFER_BIT );
			glFlush();

#include <iostream>
using namespace std;


int main ()
{
    float Circumference;
    float Diameter;
    
    cout << "Please enter diameter: ";
    cin >> Diameter;
    
    Circumference = 3.14f * Diameter;   // use f suffix to force float type
    
    cout << " Circumference is " << Circumference << endl;
    
    return 0;
    }

#define Circumference c
#define Foo 10

cout <<  Circumference << "  " << Foo << end;

cout << c << " " << 10

int main( void )
{
  float Diameter;
  float Circumference;

  cout << "Please enter diameter: ";
  cin >> Diameter;

  Circumference = 3.14 * Diameter;

  cout << " Circumference is " << Circumference << endl;

  return 0;
}