test texture wrap modes

progs/tests/texwrap.c

@@ -0,0 +1,181 @@
+/* $Id: texwrap.c,v 1.1 2001/03/26 19:45:57 brianp Exp $ */
+
+/*
+ * Test texture wrap modes.
+ *
+ * Brian Paul   March 2001
+ */
+
+
+#define GL_GLEXT_PROTOTYPES
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <GL/glut.h>
+
+
+#ifndef GL_CLAMP_TO_BORDER_ARB
+#define GL_CLAMP_TO_BORDER_ARB 0x812D
+#endif
+
+
+#define SIZE 4
+static GLubyte TexImage[SIZE+2][SIZE+2][4];
+
+
+static void
+PrintString(const char *s)
+{
+   while (*s) {
+      glutBitmapCharacter(GLUT_BITMAP_8_BY_13, (int) *s);
+      s++;
+   }
+}
+
+
+static void Display( void )
+{
+   static const GLenum modes[] = {
+      GL_REPEAT,
+      GL_CLAMP,
+      GL_CLAMP_TO_EDGE,
+      GL_CLAMP_TO_BORDER_ARB
+   };
+   static const char *names[] = {
+      "GL_REPEAT",
+      "GL_CLAMP",
+      "GL_CLAMP_TO_EDGE",
+      "GL_CLAMP_TO_BORDER_ARB"
+   };
+
+   GLint i, j;
+   GLint numModes;
+
+   numModes = glutExtensionSupported("GL_ARB_texture_border_clamp") ? 4 : 3;
+
+   glClearColor(0.5, 0.5, 0.5, 1.0);
+   glClear( GL_COLOR_BUFFER_BIT );
+
+#if 0
+   /* draw texture as image */
+   glDisable(GL_TEXTURE_2D);
+   glWindowPos2iMESA(1, 1);
+   glDrawPixels(6, 6, GL_RGBA, GL_UNSIGNED_BYTE, (void *) TexImage);
+#endif
+
+   glEnable(GL_TEXTURE_2D);
+
+   /* loop over min/mag filters */
+   for (i = 0; i < 2; i++) {
+      if (i) {
+         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+      }
+      else {
+         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+      }
+
+      /* loop over border modes */
+      for (j = 0; j < numModes; j++) {
+         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, modes[j]);
+         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, modes[j]);
+
+         glPushMatrix();
+            glTranslatef(j * 150 + 10, i * 150 + 25, 0);
+
+            glBegin(GL_POLYGON);
+            glTexCoord2f(-0.2, -0.2);  glVertex2f(  0,   0);
+            glTexCoord2f( 1.2, -0.2);  glVertex2f(140,   0);
+            glTexCoord2f( 1.2,  1.2);  glVertex2f(140, 140);
+            glTexCoord2f(-0.2,  1.2);  glVertex2f(  0, 140);
+            glEnd();
+
+         glPopMatrix();
+      }
+   }
+
+   glDisable(GL_TEXTURE_2D);
+   for (i = 0; i < numModes; i++) {
+      glWindowPos2iMESA( i * 150 + 10, 5);
+      PrintString(names[i]);
+   }
+
+   glutSwapBuffers();
+}
+
+
+static void Reshape( int width, int height )
+{
+   glViewport( 0, 0, width, height );
+   glMatrixMode( GL_PROJECTION );
+   glLoadIdentity();
+   glOrtho(0, width, 0, height, -1, 1);
+   glMatrixMode( GL_MODELVIEW );
+   glLoadIdentity();
+}
+
+
+static void Key( unsigned char key, int x, int y )
+{
+   (void) x;
+   (void) y;
+   switch (key) {
+      case 27:
+         exit(0);
+         break;
+   }
+   glutPostRedisplay();
+}
+
+
+static void Init( void )
+{
+   static const GLubyte border[4] = { 0, 255, 0, 255 };
+   GLint i, j;
+
+   for (i = 0; i < SIZE+2; i++) {
+      for (j = 0; j < SIZE+2; j++) {
+         if (i == 0 || j == 0 || i == SIZE+1 || j == SIZE+1) {
+            /* border color */
+            TexImage[i][j][0] = border[0];
+            TexImage[i][j][1] = border[1];
+            TexImage[i][j][2] = border[2];
+            TexImage[i][j][3] = border[3];
+         }
+         else if ((i + j) & 1) {
+            /* white */
+            TexImage[i][j][0] = 255;
+            TexImage[i][j][1] = 255;
+            TexImage[i][j][2] = 255;
+            TexImage[i][j][3] = 255;
+         }
+         else {
+            /* black */
+            TexImage[i][j][0] = 0;
+            TexImage[i][j][1] = 0;
+            TexImage[i][j][2] = 0;
+            TexImage[i][j][3] = 0;
+         }
+      }
+   }
+
+   glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, SIZE+2, SIZE+2, 1,
+                GL_RGBA, GL_UNSIGNED_BYTE, (void *) TexImage);
+}
+
+
+int main( int argc, char *argv[] )
+{
+   glutInit( &argc, argv );
+   glutInitWindowPosition( 0, 0 );
+   glutInitWindowSize( 650, 340 );
+   glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE );
+   glutCreateWindow(argv[0]);
+   glutReshapeFunc( Reshape );
+   glutKeyboardFunc( Key );
+   glutDisplayFunc( Display );
+   Init();
+   glutMainLoop();
+   return 0;
+}