1 files changed, 170 insertions, 0 deletions
diff --git a/progs/trivial/quad-tex-alpha.c b/progs/trivial/quad-tex-alpha.c
new file mode 100644
index 0000000000..cd73f013eb
--- /dev/null
+++ b/progs/trivial/quad-tex-alpha.c
@@ -0,0 +1,170 @@
+/*
+ * Copyright (c) 1991, 1992, 1993 Silicon Graphics, Inc.
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and
+ * its documentation for any purpose is hereby granted without fee, provided
+ * that (i) the above copyright notices and this permission notice appear in
+ * all copies of the software and related documentation, and (ii) the name of
+ * Silicon Graphics may not be used in any advertising or
+ * publicity relating to the software without the specific, prior written
+ * permission of Silicon Graphics.
+ *
+ * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF
+ * ANY KIND,
+ * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
+ * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * IN NO EVENT SHALL SILICON GRAPHICS BE LIABLE FOR
+ * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
+ * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
+ * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
+ * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+ * OF THIS SOFTWARE.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <GL/glut.h>
+
+
+#define CI_OFFSET_1 16
+#define CI_OFFSET_2 32
+
+
+GLenum doubleBuffer;
+
+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));
+
+    glClearColor(0.0, 0.0, 1.0, 0.0);
+
+#define SIZE 16
+   {
+      GLubyte tex2d[SIZE][SIZE][4];
+      GLint s, t;
+
+      for (s = 0; s < SIZE; s++) {
+	 for (t = 0; t < SIZE; t++) {
+	    tex2d[t][s][0] = (s < SIZE/2) ? 0 : 255;
+	    tex2d[t][s][1] = (t < SIZE/2) ? 0 : 255;
+	    tex2d[t][s][2] = 0;
+	    tex2d[t][s][3] = ((t^s) & 3) * 63;
+	 }
+      }
+
+      glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
+      glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_R, GL_REPEAT);
+      glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+      glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+
+      glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+      glTexImage2D(GL_TEXTURE_2D, 0, 4, SIZE, SIZE, 0,
+		   GL_RGBA, GL_UNSIGNED_BYTE, tex2d);
+      glPixelStorei(GL_UNPACK_ALIGNMENT, 4);
+      glEnable(GL_TEXTURE_2D);
+   }
+}
+
+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, -0.5, 1000.0);
+    glMatrixMode(GL_MODELVIEW);
+}
+
+static void Key(unsigned char key, int x, int y)
+{
+
+    switch (key) {
+      case 27:
+	exit(1);
+      default:
+	return;
+    }
+
+    glutPostRedisplay();
+}
+
+static void Draw(void)
+{
+   glClear(GL_COLOR_BUFFER_BIT); 
+
+   glDisable(GL_DEPTH_TEST);
+   glDisable(GL_STENCIL_TEST);
+   glEnable(GL_ALPHA_TEST);
+   glAlphaFunc(GL_GEQUAL, 0.5);
+
+   glBegin(GL_QUADS);
+   glTexCoord2f(1,0); 
+   glVertex3f( 0.9, -0.9, -30.0);
+   glTexCoord2f(1,1); 
+   glVertex3f( 0.9,  0.9, -30.0);
+   glTexCoord2f(0,1); 
+   glVertex3f(-0.9,  0.9, -30.0);
+   glTexCoord2f(0,0); 
+   glVertex3f(-0.9,  -0.9, -30.0);
+   glEnd();
+
+
+   glFlush();
+
+   if (doubleBuffer) {
+      glutSwapBuffers();
+   }
+}
+
+static GLenum Args(int argc, char **argv)
+{
+    GLint i;
+
+    doubleBuffer = GL_FALSE;
+
+    for (i = 1; i < argc; i++) {
+        if (strcmp(argv[i], "-sb") == 0) {
+	    doubleBuffer = GL_FALSE;
+	} else if (strcmp(argv[i], "-db") == 0) {
+	    doubleBuffer = GL_TRUE;
+	} else {
+	    fprintf(stderr, "%s (Bad option).\n", argv[i]);
+	    return GL_FALSE;
+	}
+    }
+    return GL_TRUE;
+}
+
+int main(int argc, char **argv)
+{
+    GLenum type;
+
+    glutInit(&argc, argv);
+
+    if (Args(argc, argv) == GL_FALSE) {
+	exit(1);
+    }
+
+    glutInitWindowPosition(100, 0); glutInitWindowSize( 250, 250);
+
+    type = GLUT_RGB;
+    type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
+    glutInitDisplayMode(type);
+
+    if (glutCreateWindow("First Tri") == GL_FALSE) {
+	exit(1);
+    }
+
+    Init();
+
+    glutReshapeFunc(Reshape);
+    glutKeyboardFunc(Key);
+    glutDisplayFunc(Draw);
+    glutMainLoop();
+	return 0;
+}