1 files changed, 116 insertions, 0 deletions
diff --git a/progs/trivial/tri-point-line-clipped.c b/progs/trivial/tri-point-line-clipped.c
new file mode 100644
index 0000000000..f8c1015f5f
--- /dev/null
+++ b/progs/trivial/tri-point-line-clipped.c
@@ -0,0 +1,116 @@
+/**
+ * Test frustum/user clipping w/ glPolygonMode LINE/POINT.
+ *
+ * The bottom/left and bottom/right verts are outside the frustum and clipped.
+ * The top vertex is clipped by a user clipping plane.
+ *
+ * A filled gray reference triangle is shown underneath the points/lines.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <GL/glut.h>
+
+
+static int win;
+
+
+static void
+ColorTri(void)
+{
+   glBegin(GL_TRIANGLES);
+   glColor3f(1, 0, 0);   glVertex3f(-1.5, -0.8, 0.0);
+   glColor3f(0, 1, 0);   glVertex3f( 1.5, -0.8, 0.0);
+   glColor3f(0, 0, 1);   glVertex3f( 0.0,  0.9, 0.0);
+   glEnd();
+}
+
+
+static void
+GrayTri(void)
+{
+   glColor3f(0.3, 0.3, 0.3);
+   glBegin(GL_TRIANGLES);
+   glVertex3f(-1.5, -0.8, 0.0);
+   glVertex3f( 1.5, -0.8, 0.0);
+   glVertex3f( 0.0,  0.9, 0.0);
+   glEnd();
+}
+
+
+static void
+Draw(void)
+{
+   static const GLdouble plane[4] = { 0, -1.0, 0, 0.5 };
+
+   glClear(GL_COLOR_BUFFER_BIT); 
+
+   glPointSize(13.0);
+   glLineWidth(5.0);
+
+   glClipPlane(GL_CLIP_PLANE0, plane);
+   glEnable(GL_CLIP_PLANE0);
+
+   glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
+   GrayTri();
+
+   glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
+   ColorTri();
+
+   glPolygonMode(GL_FRONT_AND_BACK, GL_POINT);
+   ColorTri();
+
+   glutSwapBuffers();
+}
+
+
+static void Reshape(int width, int height)
+{
+   glViewport(0, 0, (GLint)width, (GLint)height);
+   glMatrixMode(GL_PROJECTION);
+   glLoadIdentity();
+   glOrtho(-1.0, 1.0, -1.0, 1.0, -1.0, 1.0);
+   glMatrixMode(GL_MODELVIEW);
+}
+
+
+static void
+Key(unsigned char key, int x, int y)
+{
+   if (key == 27) {
+      glutDestroyWindow(win);
+      exit(0);
+   }
+   else {
+      glutPostRedisplay();
+   }
+}
+
+
+static void
+Init(void)
+{
+   fprintf(stderr, "GL_RENDERER   = %s\n", (char *) glGetString(GL_RENDERER));
+   fprintf(stderr, "GL_VERSION    = %s\n", (char *) glGetString(GL_VERSION));
+   fprintf(stderr, "GL_VENDOR     = %s\n", (char *) glGetString(GL_VENDOR));
+   fflush(stderr);
+}
+
+
+int
+main(int argc, char **argv)
+{
+   glutInitWindowSize(300, 300);
+   glutInit(&argc, argv);
+   glutInitDisplayMode(GLUT_DOUBLE | GLUT_DEPTH);
+   win = glutCreateWindow(*argv);
+   if (!win) {
+      return 1;
+   }
+   Init();
+   glutReshapeFunc(Reshape);
+   glutKeyboardFunc(Key);
+   glutDisplayFunc(Draw);
+   glutMainLoop();
+   return 0;
+}