1 files changed, 165 insertions, 0 deletions
diff --git a/progs/tests/texcompsub.c b/progs/tests/texcompsub.c
new file mode 100644
index 0000000000..79a5f958a1
--- /dev/null
+++ b/progs/tests/texcompsub.c
@@ -0,0 +1,165 @@
+/*
+ * Test texture compression.
+ */
+
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <GL/glew.h>
+#include <GL/glut.h>
+
+#include "texcomp_image.h"
+
+static int ImgWidth = 512;
+static int ImgHeight = 512;
+static GLenum CompFormat = GL_COMPRESSED_RGBA_S3TC_DXT1_EXT;
+static GLfloat EyeDist = 5.0;
+static GLfloat Rot = 0.0;
+const GLenum Target = GL_TEXTURE_2D;
+
+
+static void
+CheckError(int line)
+{
+   GLenum err = glGetError();
+   if (err) {
+      printf("GL Error %d at line %d\n", (int) err, line);
+   }
+}
+
+static void
+LoadCompressedImage(void)
+{
+   const GLenum filter = GL_LINEAR;
+   glTexImage2D(Target, 0, CompFormat, ImgWidth, ImgHeight, 0,
+                GL_RGB, GL_UNSIGNED_BYTE, NULL);
+
+   /* bottom half */
+   glCompressedTexSubImage2DARB(Target, 0,
+                                0, 0, /* pos */
+                                ImgWidth, ImgHeight / 2,
+                                CompFormat, ImgSize / 2, ImgData + ImgSize / 2);
+   /* top half */
+   glCompressedTexSubImage2DARB(Target, 0,
+                                0, ImgHeight / 2, /* pos */
+                                ImgWidth, ImgHeight / 2,
+                                CompFormat, ImgSize / 2, ImgData);
+
+   glTexParameteri(Target, GL_TEXTURE_MIN_FILTER, filter);
+   glTexParameteri(Target, GL_TEXTURE_MAG_FILTER, filter);
+}
+
+static void
+Init()
+{
+   GLint numFormats, formats[100];
+   GLint p;
+
+   if (!glutExtensionSupported("GL_ARB_texture_compression")) {
+      printf("Sorry, GL_ARB_texture_compression is required.\n");
+      exit(1);
+   }
+   if (!glutExtensionSupported("GL_EXT_texture_compression_s3tc")) {
+      printf("Sorry, GL_EXT_texture_compression_s3tc is required.\n");
+      exit(1);
+   }
+
+   printf("GL_VERSION = %s\n", (char *) glGetString(GL_VERSION));
+   printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
+
+   glGetIntegerv(GL_NUM_COMPRESSED_TEXTURE_FORMATS_ARB, &numFormats);
+   glGetIntegerv(GL_COMPRESSED_TEXTURE_FORMATS_ARB, formats);
+   printf("%d supported compression formats: ", numFormats);
+   for (p = 0; p < numFormats; p++)
+      printf("0x%x ", formats[p]);
+   printf("\n");
+
+   glEnable(GL_TEXTURE_2D);
+
+   LoadCompressedImage();
+}
+
+
+static void
+Reshape( int width, int height )
+{
+   glViewport( 0, 0, width, height );
+   glMatrixMode( GL_PROJECTION );
+   glLoadIdentity();
+   glFrustum(-1, 1, -1, 1, 4, 100);
+   glMatrixMode( GL_MODELVIEW );
+   glLoadIdentity();
+}
+
+
+static void
+Key( unsigned char key, int x, int y )
+{
+   (void) x;
+   (void) y;
+   switch (key) {
+      case 'd':
+         EyeDist -= 1.0;
+         if (EyeDist < 4.0)
+            EyeDist = 4.0;
+         break;
+      case 'D':
+         EyeDist += 1.0;
+         break;
+      case 'z':
+         Rot += 5.0;
+         break;
+      case 'Z':
+         Rot -= 5.0;
+         break;
+      case 27:
+         exit(0);
+         break;
+   }
+   glutPostRedisplay();
+}
+
+
+static void
+Draw( void )
+{
+   glClearColor(0.3, 0.3, .8, 0);
+   glClear(GL_COLOR_BUFFER_BIT);
+
+   CheckError(__LINE__);
+   glPushMatrix();
+   glTranslatef(0, 0, -(EyeDist+0.01));
+   glRotatef(Rot, 0, 0, 1);
+   glBegin(GL_POLYGON);
+   glTexCoord2f(0, 0);  glVertex2f(-1, -1);
+   glTexCoord2f(1, 0);  glVertex2f( 1, -1);
+   glTexCoord2f(1, 1);  glVertex2f( 1,  1);
+   glTexCoord2f(0, 1);  glVertex2f(-1,  1);
+   glEnd();
+   glPopMatrix();
+
+   glutSwapBuffers();
+}
+
+
+int
+main( int argc, char *argv[] )
+{
+   glutInit( &argc, argv );
+   glutInitWindowSize( 600, 600 );
+
+   glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE);
+
+   glutCreateWindow(argv[0]);
+   glewInit();
+
+   glutReshapeFunc( Reshape );
+   glutKeyboardFunc( Key );
+   glutDisplayFunc( Draw );
+
+   Init();
+
+   glutMainLoop();
+   return 0;
+}