progs/trivial: added comments

This commit is contained in:
Brian Paul
2010-03-17 16:26:41 -06:00
parent fecd4cde50
commit 0557d0a4b2

View File

@@ -77,6 +77,7 @@ static void Draw(void)
glStencilFunc(GL_ALWAYS, 1, 1);
glStencilOp(GL_KEEP, GL_KEEP, GL_REPLACE);
/* red triangle (setting stencil to 1) */
glColor3ub(200, 0, 0);
glBegin(GL_POLYGON);
glVertex3i(-4, -4, 0);
@@ -88,6 +89,7 @@ static void Draw(void)
glStencilFunc(GL_EQUAL, 1, 1);
glStencilOp(GL_INCR, GL_KEEP, GL_DECR);
/* green quad (if over red, decr stencil to 0, else incr to 1) */
glColor3ub(0, 200, 0);
glBegin(GL_POLYGON);
glVertex3i(3, 3, 0);
@@ -101,6 +103,7 @@ static void Draw(void)
glStencilFunc(GL_EQUAL, 1, 1);
glStencilOp(GL_KEEP, GL_KEEP, GL_KEEP);
/* blue quad (where stencil == 1) */
glColor3ub(0, 0, 200);
glBegin(GL_POLYGON);
glVertex3f(2.5, 2.5, 0);