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-rw-r--r--progs/trivial/tri-point-line-clipped.c116
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 00000000000..f8c1015f5f4
--- /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;
+}