Add a couple of test apps for line/unfilled polygon clipping.
diff --git a/progs/tests/lineclip.c b/progs/tests/lineclip.c
new file mode 100644
index 0000000..098f5e9
--- /dev/null
+++ b/progs/tests/lineclip.c
@@ -0,0 +1,175 @@
+/*
+ * Copyright © 2008 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ * Authors:
+ * Eric Anholt <eric@anholt.net>
+ *
+ */
+
+#include <stdlib.h>
+#include <GL/glut.h>
+
+static int win_width, win_height;
+
+static void
+line(GLfloat x1, GLfloat y1, GLfloat x2, GLfloat y2)
+{
+ glBegin(GL_LINES);
+ glVertex2f(x1, y1);
+ glVertex2f(x2, y2);
+ glEnd();
+}
+
+static void
+line3(GLfloat x1, GLfloat y1, GLfloat z1, GLfloat x2, GLfloat y2, GLfloat z2)
+{
+ glBegin(GL_LINES);
+ glVertex3f(x1, y1, z1);
+ glVertex3f(x2, y2, z2);
+ glEnd();
+}
+
+static void
+display(void)
+{
+ glClearColor(0.0, 0.0, 0.0, 0.0);
+ glClear(GL_COLOR_BUFFER_BIT);
+
+ glColor3f(1.0, 0.0, 0.0);
+ /* 2 lines clipped along xmin */
+ line(-20, win_height / 2 - 20,
+ 20, win_height / 2 - 20);
+ line( 20, win_height / 2 + 20,
+ -20, win_height / 2 + 20);
+
+ glColor3f(0.0, 1.0, 0.0);
+ /* 2 lines clipped along ymax */
+ line(win_width / 2 - 20, win_height + 20,
+ win_width / 2 - 20, win_height - 20);
+ line(win_width / 2 + 20, win_height - 20,
+ win_width / 2 + 20, win_height + 20);
+
+ glColor3f(0.0, 0.0, 1.0);
+ /* 2 lines clipped along xmax */
+ line(win_width - 20, win_height / 2 - 20,
+ win_width + 20, win_height / 2 - 20);
+ line(win_width + 20, win_height / 2 + 20,
+ win_width - 20, win_height / 2 + 20);
+
+ glColor3f(1.0, 1.0, 1.0);
+ /* 2 lines clipped along ymin */
+ line(win_width / 2 - 20, 20,
+ win_width / 2 - 20, -20);
+ line(win_width / 2 + 20, -20,
+ win_width / 2 + 20, 20);
+
+ /* 2 lines clipped along near */
+ glColor3f(1.0, 0.0, 1.0);
+ line3(win_width / 2 - 20 - 20, win_height / 2, 0.5,
+ win_width / 2 - 20 + 20, win_height / 2, -0.5);
+ line3(win_width / 2 - 20, win_height / 2 - 20, -0.5,
+ win_width / 2 - 20, win_height / 2 + 20, 0.5);
+
+ /* 2 lines clipped along far */
+ glColor3f(0.0, 1.0, 1.0);
+ line3(win_width / 2 + 20 - 20, win_height / 2, 1.5,
+ win_width / 2 + 20 + 20, win_height / 2, 0.5);
+ line3(win_width / 2 + 20, win_height / 2 - 20, 0.5,
+ win_width / 2 + 20, win_height / 2 + 20, 1.5);
+
+ /* entirely clipped along near/far */
+ glColor3f(.5, .5, .5);
+ line3(win_width / 2, win_height / 2 - 20, -0.5,
+ win_width / 2, win_height / 2 + 20, -0.5);
+ glColor3f(.5, .5, .5);
+ line3(win_width / 2, win_height / 2 - 20, 1.5,
+ win_width / 2, win_height / 2 + 20, 1.5);
+
+ glColor3f(1.0, 1.0, 0.0);
+ /* lines clipped along both x and y limits */
+ line(-5, 20,
+ 20, -5); /* xmin, ymin */
+ line(-5, win_height - 20,
+ 20, win_height + 5); /* xmin, ymax */
+ line(win_width - 20, -5,
+ win_width + 5, 20); /* xmax, ymin */
+ line(win_width - 20, win_height + 5,
+ win_width + 5, win_height - 20); /* xmax, ymax */
+
+ glutSwapBuffers();
+}
+
+static void
+reshape(int width, int height)
+{
+ win_width = width;
+ win_height = height;
+ glViewport(0, 0, width, height);
+
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+ glOrtho(0, win_width, 0, win_height, 0.0, -1.0);
+
+ glMatrixMode(GL_MODELVIEW);
+ glLoadIdentity();
+ glTranslatef(.25, .25, 0);
+}
+
+static void key( unsigned char key, int x, int y )
+{
+ (void) x;
+ (void) y;
+
+ switch (key) {
+ case 27: /* esc */
+ exit(0);
+ break;
+ }
+
+ glutPostRedisplay();
+}
+
+static void
+init(void)
+{
+}
+
+int
+main(int argc, char *argv[])
+{
+ win_width = 200;
+ win_height = 200;
+
+ glutInit(&argc, argv);
+ glutInitWindowPosition(0, 0);
+ glutInitWindowSize(win_width, win_height);
+ glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);
+ glutCreateWindow(argv[0]);
+ glutReshapeFunc(reshape);
+ glutKeyboardFunc(key);
+ glutDisplayFunc(display);
+
+ init();
+
+ glutMainLoop();
+ return 0;
+}