From 073c20befa28177cf1276bfb8c75f6638d588580 Mon Sep 17 00:00:00 2001
From: Brian Paul <brianp@vmware.com>
Date: Tue, 9 Jun 2009 15:05:36 -0600
Subject: [PATCH] tests: also test glGetTexImage with render to texture

Also, adjust texture dims for the original test.
And use GLEW.
---
 progs/tests/getteximage.c | 114 ++++++++++++++++++++++++++++++++++----
 1 file changed, 103 insertions(+), 11 deletions(-)

diff --git a/progs/tests/getteximage.c b/progs/tests/getteximage.c
index c8705d5052b..f0160f5863a 100644
--- a/progs/tests/getteximage.c
+++ b/progs/tests/getteximage.c
@@ -8,6 +8,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <math.h>
+#include <GL/glew.h>
 #include <GL/glut.h>
 
 static int Win;
@@ -17,17 +18,22 @@ static void
 TestGetTexImage(void)
 {
    GLuint iter;
+   GLubyte *data = (GLubyte *) malloc(1024 * 1024 * 4);
+   GLubyte *data2 = (GLubyte *) malloc(1024 * 1024 * 4);
 
-   for (iter = 0; iter < 20; iter++) {
-      GLint p = (iter % 6) + 4;
+   glEnable(GL_TEXTURE_2D);
+
+   printf("glTexImage2D + glGetTexImage:\n");
+
+   for (iter = 0; iter < 8; iter++) {
+      GLint p = (iter % 8) + 3;
       GLint w = (1 << p);
       GLint h = (1 << p);
-      GLubyte data[512*512*4];
-      GLubyte data2[512*512*4];
       GLuint i;
       GLint level = 0;
 
-      printf("Testing %d x %d tex image\n", w, h);
+      printf("  Testing %d x %d tex image\n", w, h);
+
       /* fill data */
       for (i = 0; i < w * h * 4; i++) {
          data[i] = i & 0xff;
@@ -47,17 +53,100 @@ TestGetTexImage(void)
       /* compare */
       for (i = 0; i < w * h * 4; i++) {
          if (data2[i] != data[i]) {
-            printf("Failure!\n");
+            printf("glTexImage + glGetTexImage failure!\n");
+            printf("Expected value %d, found %d\n", data[i], data2[i]);
             abort();
          }
       }
    }
+
    printf("Passed\n");
-   glutDestroyWindow(Win);
-   exit(0);
+   glDisable(GL_TEXTURE_2D);
+   free(data);
+   free(data2);
+}
+
+
+static GLboolean
+ColorsEqual(const GLubyte ref[4], const GLubyte act[4])
+{
+   if (abs((int) ref[0] - (int) act[0]) > 1 ||
+       abs((int) ref[1] - (int) act[1]) > 1 ||
+       abs((int) ref[2] - (int) act[2]) > 1 ||
+       abs((int) ref[3] - (int) act[3]) > 1) {
+      printf("expected %d %d %d %d\n", ref[0], ref[1], ref[2], ref[3]);
+      printf("found    %d %d %d %d\n", act[0], act[1], act[2], act[3]);
+      return GL_FALSE;
+   }
+   return GL_TRUE;
 }
 
 
+static void
+TestGetTexImageRTT(void)
+{
+   GLuint iter;
+   GLuint fb, tex;
+   GLint w = 512;
+   GLint h = 256;
+   GLint level = 0;
+   
+   glGenTextures(1, &tex);
+   glGenFramebuffersEXT(1, &fb);
+
+   glBindTexture(GL_TEXTURE_2D, tex);
+   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+   glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, w, h, 0,
+                GL_RGBA, GL_UNSIGNED_BYTE, NULL);
+
+   glBindFramebuffer(GL_FRAMEBUFFER_EXT, fb);
+   glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
+                             GL_TEXTURE_2D, tex, level);
+
+   printf("Render to texture + glGetTexImage:\n");
+   printf("  Testing %d x %d tex image\n", w, h);
+   for (iter = 0; iter < 8; iter++) {
+      GLubyte color[4];
+      GLubyte *data2 = (GLubyte *) malloc(w * h * 4);
+      GLuint i;
+
+      /* random clear color */
+      for (i = 0; i < 4; i++) {
+         color[i] = rand() % 256;
+      }
+
+      glClearColor(color[0] / 255.0,
+                   color[1] / 255.0,
+                   color[2] / 255.0,
+                   color[3] / 255.0);
+
+      glClear(GL_COLOR_BUFFER_BIT);
+
+      /* get */
+      glGetTexImage(GL_TEXTURE_2D, level, GL_RGBA, GL_UNSIGNED_BYTE, data2);
+
+      /* compare */
+      for (i = 0; i < w * h; i += 4) {
+         if (!ColorsEqual(color, data2 + i * 4)) {
+            printf("Render to texture failure!\n");
+            abort();
+         }
+      }
+
+      free(data2);
+   }
+
+   glBindFramebuffer(GL_FRAMEBUFFER_EXT, 0);
+   glDeleteFramebuffersEXT(1, &fb);
+   glDeleteTextures(1, &tex);
+
+   printf("Passed\n");
+}
+
+
+
+
 static void
 Draw(void)
 {
@@ -65,6 +154,11 @@ Draw(void)
 
    TestGetTexImage();
 
+   TestGetTexImageRTT();
+
+   glutDestroyWindow(Win);
+   exit(0);
+
    glutSwapBuffers();
 }
 
@@ -100,9 +194,6 @@ Key(unsigned char key, int x, int y)
 static void
 Init(void)
 {
-   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
-   glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
-   glEnable(GL_TEXTURE_2D);
 }
 
 
@@ -114,6 +205,7 @@ main(int argc, char *argv[])
    glutInitWindowSize(400, 400);
    glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);
    Win = glutCreateWindow(argv[0]);
+   glewInit();
    glutReshapeFunc(Reshape);
    glutKeyboardFunc(Key);
    glutDisplayFunc(Draw);
-- 
2.30.2