* \file stencil_twoside.c
*
* Simple test of GL_ATI_separate_stencil (or the OGL 2.0 equivalent) functionality.
- * Four squares are drawn
+ * Five squares (or six if stencil wrap is available) are drawn
* with different stencil modes, but all should be rendered with the same
* final color.
*/
#include <GL/glut.h>
static int use20syntax = 1;
-static int Width = 550;
+static int Width = 650;
static int Height = 200;
static const GLfloat Near = 5.0, Far = 25.0;
*/
glDisable(GL_STENCIL_TEST);
- glTranslatef(-6.0, 0, 0);
+ glTranslatef(-7.0, 0, 0);
glBegin(GL_QUADS);
glColor3f( 0.5, 0.5, 0.5 );
glVertex2f(-1, -1);
else {
stencil_func_separate_ati(GL_ALWAYS, GL_ALWAYS, 0, ~0);
}
- stencil_op_separate(GL_FRONT, GL_KEEP, GL_KEEP, GL_DECR);
- stencil_op_separate(GL_BACK, GL_KEEP, GL_KEEP, GL_INCR);
+ stencil_op_separate(GL_FRONT, GL_KEEP, GL_KEEP, GL_INCR);
+ stencil_op_separate(GL_BACK, GL_KEEP, GL_KEEP, GL_DECR);
glTranslatef(3.0, 0, 0);
glBegin(GL_QUADS);
glVertex2f(-1, 1);
glEnd();
+ /*************************************************************************
+ * 6th square
+ */
+ if (glutExtensionSupported("GL_EXT_stencil_wrap")) {
+ if (use20syntax) {
+ stencil_func_separate(GL_FRONT, GL_ALWAYS, 0, ~0);
+ stencil_func_separate(GL_BACK, GL_ALWAYS, 0, ~0);
+ }
+ else {
+ stencil_func_separate_ati(GL_ALWAYS, GL_ALWAYS, 0, ~0);
+ }
+ stencil_op_separate(GL_FRONT, GL_KEEP, GL_KEEP, GL_KEEP);
+ stencil_op_separate(GL_BACK, GL_KEEP, GL_KEEP, GL_INCR_WRAP);
+
+ glTranslatef(3.0, 0, 0);
+ glBegin(GL_QUADS);
+ glColor3f( 0.9, 0.9, 0.9 );
+ for ( i = 0 ; i < (max_stencil + 5) ; i++ ) {
+ /* this should be back facing */
+ glVertex2f(-1, -1);
+ glVertex2f(-1, 1);
+ glVertex2f( 1, 1);
+ glVertex2f( 1, -1);
+ /* this should be front facing */
+ glVertex2f(-1, -1);
+ glVertex2f( 1, -1);
+ glVertex2f( 1, 1);
+ glVertex2f(-1, 1);
+ }
+ glEnd();
+
+ glStencilFunc(GL_EQUAL, 260 - 255, ~0);
+ glBegin(GL_QUADS);
+ glColor3f( 0.5, 0.5, 0.5 );
+ glVertex2f(-1, -1);
+ glVertex2f( 1, -1);
+ glVertex2f( 1, 1);
+ glVertex2f(-1, 1);
+ glEnd();
+ }
+
glPopMatrix();
glutSwapBuffers();
stencil_func_separate_ati = (PFNGLSTENCILFUNCSEPARATEATIPROC) glutGetProcAddress( "glStencilFuncSeparateATI" );
stencil_op_separate = (PFNGLSTENCILOPSEPARATEPROC) glutGetProcAddress( "glStencilOpSeparate" );
- printf("\nAll 5 squares should be the same color.\n");
+ printf("\nAll 5 (or 6) squares should be the same color.\n");
}