1 files changed, 268 insertions, 0 deletions
diff --git a/progs/trivial/tri-fbo-tex.c b/progs/trivial/tri-fbo-tex.c
new file mode 100644
index 0000000000..253f9310db
--- /dev/null
+++ b/progs/trivial/tri-fbo-tex.c
@@ -0,0 +1,268 @@
+/*
+ * Test GL_EXT_framebuffer_object render-to-texture
+ *
+ * Draw a teapot into a texture image with stenciling.
+ * Then draw a textured quad using that texture.
+ *
+ * Brian Paul
+ * 18 Apr 2005
+ */
+
+
+#include <GL/glew.h>
+#include <GL/glut.h>
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+
+/* For debug */
+
+
+static int Win = 0;
+static int Width = 512, Height = 512;
+
+static GLenum TexTarget = GL_TEXTURE_2D;
+static int TexWidth = 512, TexHeight = 512;
+
+static GLuint MyFB;
+static GLuint TexObj;
+static GLboolean Anim = GL_FALSE;
+static GLfloat Rot = 0.0;
+static GLuint TextureLevel = 0;  /* which texture level to render to */
+static GLenum TexIntFormat = GL_RGB; /* either GL_RGB or GL_RGBA */
+
+
+static void
+CheckError(int line)
+{
+   GLenum err = glGetError();
+   if (err) {
+      printf("GL Error 0x%x at line %d\n", (int) err, line);
+   }
+}
+
+
+static void
+Idle(void)
+{
+   Rot = glutGet(GLUT_ELAPSED_TIME) * 0.1;
+   glutPostRedisplay();
+}
+
+
+static void
+RenderTexture(void)
+{
+   GLenum status;
+
+   glMatrixMode(GL_PROJECTION);
+   glLoadIdentity();
+   glOrtho(-1.0, 1.0, -1.0, 1.0, 5.0, 25.0);
+   glMatrixMode(GL_MODELVIEW);
+   glLoadIdentity();
+   glTranslatef(0.0, 0.0, -15.0);
+
+   if (1) {
+      /* draw to texture image */
+      glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, MyFB);
+
+      status = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT);
+      if (status != GL_FRAMEBUFFER_COMPLETE_EXT) {
+	 printf("Framebuffer incomplete!!!\n");
+      }
+
+      glViewport(0, 0, TexWidth, TexHeight);
+
+      glClearColor(0.5, 0.5, 1.0, 0.0);
+      glClear(GL_COLOR_BUFFER_BIT);
+      
+      CheckError(__LINE__);
+
+      glBegin(GL_POLYGON);
+      glColor3f(1, 0, 0);
+      glVertex2f(-1, -1);
+      glColor3f(0, 1, 0);
+      glVertex2f(1, -1);
+      glColor3f(0, 0, 1);
+      glVertex2f(0, 1);
+      glEnd();
+
+      /* Bind normal framebuffer */
+      glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
+   }
+   else {
+   }
+
+   CheckError(__LINE__);
+}
+
+
+
+static void
+Display(void)
+{
+   float ar = (float) Width / (float) Height;
+
+   RenderTexture();
+   
+   /* draw textured quad in the window */
+   glMatrixMode(GL_PROJECTION);
+   glLoadIdentity();
+   glFrustum(-ar, ar, -1.0, 1.0, 5.0, 25.0);
+   glMatrixMode(GL_MODELVIEW);
+   glLoadIdentity();
+   glTranslatef(0.0, 0.0, -7.0);
+
+   glViewport(0, 0, Width, Height);
+
+   glClearColor(0.25, 0.25, 0.25, 0);
+   glClear(GL_COLOR_BUFFER_BIT);
+
+   glPushMatrix();
+   glRotatef(Rot, 0, 1, 0);
+   glEnable(TexTarget);
+   glBindTexture(TexTarget, TexObj);
+
+   {
+      glBegin(GL_POLYGON);
+      glColor3f(0.25, 0.25, 0.25);
+      glTexCoord2f(0, 0);
+      glVertex2f(-1, -1);
+      glTexCoord2f(1, 0);
+      glVertex2f(1, -1);
+      glColor3f(1.0, 1.0, 1.0);
+      glTexCoord2f(1, 1);
+      glVertex2f(1, 1);
+      glTexCoord2f(0, 1);
+      glVertex2f(-1, 1);
+      glEnd();
+   }
+
+   glPopMatrix();
+   glDisable(TexTarget);
+
+   glutSwapBuffers();
+   CheckError(__LINE__);
+}
+
+
+static void
+Reshape(int width, int height)
+{
+   glViewport(0, 0, width, height);
+   Width = width;
+   Height = height;
+}
+
+
+static void
+CleanUp(void)
+{
+   glDeleteFramebuffersEXT(1, &MyFB);
+
+   glDeleteTextures(1, &TexObj);
+
+   glutDestroyWindow(Win);
+
+   exit(0);
+}
+
+
+static void
+Key(unsigned char key, int x, int y)
+{
+   (void) x;
+   (void) y;
+   switch (key) {
+      case 'a':
+         Anim = !Anim;
+         if (Anim)
+            glutIdleFunc(Idle);
+         else
+            glutIdleFunc(NULL);
+         break;
+      case 's':
+         Rot += 2.0;
+         break;
+      case 27:
+         CleanUp();
+         break;
+   }
+   glutPostRedisplay();
+}
+
+
+static void
+Init(int argc, char *argv[])
+{
+   static const GLfloat mat[4] = { 1.0, 0.5, 0.5, 1.0 };
+   GLint i;
+
+   if (!glutExtensionSupported("GL_EXT_framebuffer_object")) {
+      printf("GL_EXT_framebuffer_object not found!\n");
+      exit(0);
+   }
+
+   printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
+
+
+   /* Make texture object/image */
+   glGenTextures(1, &TexObj);
+   glBindTexture(TexTarget, TexObj);
+   glTexParameteri(TexTarget, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+   glTexParameteri(TexTarget, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+   glTexParameteri(TexTarget, GL_TEXTURE_BASE_LEVEL, TextureLevel);
+   glTexParameteri(TexTarget, GL_TEXTURE_MAX_LEVEL, TextureLevel);
+
+   glTexImage2D(TexTarget, 0, TexIntFormat, TexWidth, TexHeight, 0,
+                GL_RGBA, GL_UNSIGNED_BYTE, NULL);
+
+
+   glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
+
+
+
+
+   /* gen framebuffer id, delete it, do some assertions, just for testing */
+   glGenFramebuffersEXT(1, &MyFB);
+   glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, MyFB);
+   assert(glIsFramebufferEXT(MyFB));
+
+
+   CheckError(__LINE__);
+
+   /* Render color to texture */
+   glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
+                             TexTarget, TexObj, TextureLevel);
+
+
+
+   CheckError(__LINE__);
+
+   /* bind regular framebuffer */
+   glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
+
+
+}
+
+
+int
+main(int argc, char *argv[])
+{
+   glutInit(&argc, argv);
+   glutInitWindowPosition(0, 0);
+   glutInitWindowSize(Width, Height);
+   glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);
+   Win = glutCreateWindow(argv[0]);
+   glewInit();
+   glutReshapeFunc(Reshape);
+   glutKeyboardFunc(Key);
+   glutDisplayFunc(Display);
+   if (Anim)
+      glutIdleFunc(Idle);
+   Init(argc, argv);
+   glutMainLoop();
+   return 0;
+}