1 files changed, 364 insertions, 0 deletions
diff --git a/progs/tests/drawbuffers2.c b/progs/tests/drawbuffers2.c
new file mode 100644
index 00000000000..7b8cc5ca6a3
--- /dev/null
+++ b/progs/tests/drawbuffers2.c
@@ -0,0 +1,364 @@
+/*
+ * Test GL_ARB_draw_buffers2, GL_ARB_draw_buffers, GL_EXT_framebuffer_object
+ * and GLSL's gl_FragData[].
+ *
+ * We draw to two color buffers and show the left half of the first
+ * color buffer on the left side of the window, and show the right
+ * half of the second color buffer on the right side of the window.
+ *
+ * Different color masks are used for the two color buffers.
+ * Blending is enabled for the second buffer only.
+ *
+ * Brian Paul
+ * 31 Dec 2009
+ */
+
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <GL/glew.h>
+#include <GL/glut.h>
+#include "extfuncs.h"
+
+static int Win;
+static int Width = 400, Height = 400;
+static GLuint FBobject, RBobjects[3];
+static GLfloat Xrot = 0.0, Yrot = 0.0;
+static GLuint Program;
+static GLboolean Anim = GL_TRUE;
+
+
+static void
+CheckError(int line)
+{
+   GLenum err = glGetError();
+   if (err) {
+      printf("GL Error 0x%x at line %d\n", (int) err, line);
+   }
+}
+
+
+static void
+Display(void)
+{
+   GLubyte *buffer = malloc(Width * Height * 4);
+   static const GLenum buffers[2] = {
+      GL_COLOR_ATTACHMENT0_EXT,
+      GL_COLOR_ATTACHMENT1_EXT
+   };
+
+   glUseProgram_func(Program);
+
+   glEnable(GL_DEPTH_TEST);
+
+   /* draw to user framebuffer */
+   glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, FBobject);
+
+   /* Clear color buffer 0 (blue) */
+   glDrawBuffer(GL_COLOR_ATTACHMENT0_EXT);
+   glClear(GL_COLOR_BUFFER_BIT);
+
+   /* Clear color buffer 1 (1 - blue) */
+   glDrawBuffer(GL_COLOR_ATTACHMENT1_EXT);
+   glClear(GL_COLOR_BUFFER_BIT);
+
+   glClear(GL_DEPTH_BUFFER_BIT);
+
+   /* draw to two buffers w/ fragment shader */
+   glDrawBuffersARB(2, buffers);
+
+   /* different color masks for each buffer */
+   if (1) {
+   glColorMaskIndexedEXT(0, GL_TRUE, GL_FALSE, GL_FALSE, GL_FALSE);
+   glColorMaskIndexedEXT(1, GL_FALSE, GL_TRUE, GL_FALSE, GL_FALSE);
+   }
+
+   glPushMatrix();
+   glRotatef(Xrot, 1, 0, 0);
+   glRotatef(Yrot, 0, 1, 0);
+   glPushMatrix();
+   glTranslatef(1, 0, 0);
+   glutSolidTorus(1.0, 2.0, 10, 20);
+   glPopMatrix();
+   glPushMatrix();
+   glTranslatef(-1, 0, 0);
+   glRotatef(90, 1, 0, 0);
+   glutSolidTorus(1.0, 2.0, 10, 20);
+   glPopMatrix();
+   glPopMatrix();
+
+   /* restore default color masks */
+   glColorMaskIndexedEXT(0, GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
+   glColorMaskIndexedEXT(1, GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
+
+   /* read from user framebuffer */
+   /* left half = colorbuffer 0 */
+   glReadBuffer(GL_COLOR_ATTACHMENT0_EXT);
+   glPixelStorei(GL_PACK_ROW_LENGTH, Width);
+   glPixelStorei(GL_PACK_SKIP_PIXELS, 0);
+   glReadPixels(0, 0, Width / 2, Height, GL_RGBA, GL_UNSIGNED_BYTE,
+                buffer);
+
+   /* right half = colorbuffer 1 */
+   glReadBuffer(GL_COLOR_ATTACHMENT1_EXT);
+   glPixelStorei(GL_PACK_SKIP_PIXELS, Width / 2);
+   glReadPixels(Width / 2, 0, Width - Width / 2, Height,
+                GL_RGBA, GL_UNSIGNED_BYTE,
+                buffer);
+
+   /* draw to window */
+   glUseProgram_func(0);
+   glDisable(GL_DEPTH_TEST);
+   glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
+   glWindowPos2iARB(0, 0);
+   glDrawPixels(Width, Height, GL_RGBA, GL_UNSIGNED_BYTE, buffer);
+
+   free(buffer);
+   glutSwapBuffers();
+   CheckError(__LINE__);
+}
+
+
+static void
+Idle(void)
+{
+   Xrot = glutGet(GLUT_ELAPSED_TIME) * 0.05;
+   glutPostRedisplay();
+}
+
+
+static void
+Reshape(int width, int height)
+{
+   float ar = (float) width / (float) height;
+
+   glViewport(0, 0, width, height);
+   glMatrixMode(GL_PROJECTION);
+   glLoadIdentity();
+   glFrustum(-ar, ar, -1.0, 1.0, 5.0, 35.0);
+   glMatrixMode(GL_MODELVIEW);
+   glLoadIdentity();
+   glTranslatef(0.0, 0.0, -20.0);
+
+   Width = width;
+   Height = height;
+
+   glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, RBobjects[0]);
+   glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_RGB, Width, Height);
+   glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, RBobjects[1]);
+   glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_RGB, Width, Height);
+   glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, RBobjects[2]);
+   glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_DEPTH_COMPONENT,
+                            Width, Height);
+}
+
+
+static void
+CleanUp(void)
+{
+   glDeleteFramebuffersEXT(1, &FBobject);
+   glDeleteRenderbuffersEXT(3, RBobjects);
+   glutDestroyWindow(Win);
+   exit(0);
+}
+
+
+static void
+Key(unsigned char key, int x, int y)
+{
+   (void) x;
+   (void) y;
+   switch (key) {
+   case ' ':
+      Anim = !Anim;
+      glutIdleFunc(Anim ? Idle : NULL);
+      break;
+   case 'x':
+      Xrot += 5.0;
+      break;
+   case 'X':
+      Xrot -= 5.0;
+      break;
+   case 'y':
+      Yrot += 5.0;
+      break;
+   case 'Y':
+      Yrot -= 5.0;
+      break;
+   case 27:
+      CleanUp();
+      break;
+   }
+   glutPostRedisplay();
+}
+
+
+static void
+CheckExtensions(void)
+{
+   const char *req[] = {
+      "GL_EXT_framebuffer_object",
+      "GL_ARB_draw_buffers",
+      "GL_EXT_draw_buffers2"
+   };
+
+   const char *version = (const char *) glGetString(GL_VERSION);
+   GLint numBuf;
+   GLint i;
+
+   for (i = 0; i < 3; i++) {
+      if (!glutExtensionSupported(req[i])) {
+         printf("Sorry, %s extension is required!\n", req[i]);
+         exit(1);
+      }
+   }
+   if (version[0] != '2') {
+      printf("Sorry, OpenGL 2.0 is required!\n");
+      exit(1);
+   }
+
+   glGetIntegerv(GL_MAX_DRAW_BUFFERS_ARB, &numBuf);
+   printf("GL_MAX_DRAW_BUFFERS_ARB = %d\n", numBuf);
+   if (numBuf < 2) {
+      printf("Sorry, GL_MAX_DRAW_BUFFERS_ARB needs to be >= 2\n");
+      exit(1);
+   }
+
+   printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
+}
+
+
+static void
+SetupRenderbuffers(void)
+{
+   glGenFramebuffersEXT(1, &FBobject);
+   glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, FBobject);
+
+   glGenRenderbuffersEXT(3, RBobjects);
+
+   glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, RBobjects[0]);
+   glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_RGB, Width, Height);
+
+   glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, RBobjects[1]);
+   glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_RGB, Width, Height);
+
+   glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, RBobjects[2]);
+   glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_DEPTH_COMPONENT,
+                            Width, Height);
+
+   glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
+                                GL_RENDERBUFFER_EXT, RBobjects[0]);
+   glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT1_EXT,
+                                GL_RENDERBUFFER_EXT, RBobjects[1]);
+   glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT,
+                                GL_RENDERBUFFER_EXT, RBobjects[2]);
+
+   CheckError(__LINE__);
+}
+
+
+static GLuint
+LoadAndCompileShader(GLenum target, const char *text)
+{
+   GLint stat;
+   GLuint shader = glCreateShader_func(target);
+   glShaderSource_func(shader, 1, (const GLchar **) &text, NULL);
+   glCompileShader_func(shader);
+   glGetShaderiv_func(shader, GL_COMPILE_STATUS, &stat);
+   if (!stat) {
+      GLchar log[1000];
+      GLsizei len;
+      glGetShaderInfoLog_func(shader, 1000, &len, log);
+      fprintf(stderr, "drawbuffers: problem compiling shader:\n%s\n", log);
+      exit(1);
+   }
+   return shader;
+}
+
+
+static void
+CheckLink(GLuint prog)
+{
+   GLint stat;
+   glGetProgramiv_func(prog, GL_LINK_STATUS, &stat);
+   if (!stat) {
+      GLchar log[1000];
+      GLsizei len;
+      glGetProgramInfoLog_func(prog, 1000, &len, log);
+      fprintf(stderr, "drawbuffers: shader link error:\n%s\n", log);
+   }
+}
+
+
+static void
+SetupShaders(void)
+{
+   /* emit same color to both draw buffers */
+   static const char *fragShaderText =
+      "void main() {\n"
+      "   gl_FragData[0] = gl_Color; \n"
+      "   gl_FragData[1] = gl_Color; \n"
+      "}\n";
+
+   GLuint fragShader;
+
+   fragShader = LoadAndCompileShader(GL_FRAGMENT_SHADER, fragShaderText);
+   Program = glCreateProgram_func();
+
+   glAttachShader_func(Program, fragShader);
+   glLinkProgram_func(Program);
+   CheckLink(Program);
+   glUseProgram_func(Program);
+}
+
+
+static void
+SetupLighting(void)
+{
+   static const GLfloat ambient[4] = { 0.0, 0.0, 0.0, 0.0 };
+   static const GLfloat diffuse[4] = { 1.0, 1.0, 1.0, 0.75 };
+
+   glLightModelfv(GL_LIGHT_MODEL_AMBIENT, ambient);
+   glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT, ambient);
+   glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, diffuse);
+
+   glLightModeli(GL_LIGHT_MODEL_TWO_SIDE, 0);
+   glEnable(GL_LIGHT0);
+   glEnable(GL_LIGHTING);
+}
+
+
+static void
+Init(void)
+{
+   CheckExtensions();
+   GetExtensionFuncs();
+   SetupRenderbuffers();
+   SetupShaders();
+   SetupLighting();
+   glEnable(GL_DEPTH_TEST);
+
+   glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+   glEnableIndexedEXT(GL_BLEND, 1);
+}
+
+
+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();
+   glutIdleFunc(Anim ? Idle : NULL);
+   glutReshapeFunc(Reshape);
+   glutKeyboardFunc(Key);
+   glutDisplayFunc(Display);
+   Init();
+   glutMainLoop();
+   return 0;
+}