From 5a24c66915a555d72a6377e073a732ab9d6be461 Mon Sep 17 00:00:00 2001
From: Keith Whitwell <keithw@vmware.com>
Date: Fri, 6 Nov 2009 09:22:46 +0000
Subject: [PATCH] trivial: add vbo-tri, an even simpler version of tri.c

---
 progs/trivial/Makefile  |   1 +
 progs/trivial/vbo-tri.c | 131 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 132 insertions(+)
 create mode 100644 progs/trivial/vbo-tri.c

diff --git a/progs/trivial/Makefile b/progs/trivial/Makefile
index 70728616d28..e15ec33ab59 100644
--- a/progs/trivial/Makefile
+++ b/progs/trivial/Makefile
@@ -153,6 +153,7 @@ SOURCES = \
 	tristrip-clip.c \
 	tristrip-flat.c \
 	tristrip.c \
+	vbo-tri.c \
 	vbo-drawarrays.c \
 	vbo-noninterleaved.c \
 	vbo-drawelements.c \
diff --git a/progs/trivial/vbo-tri.c b/progs/trivial/vbo-tri.c
new file mode 100644
index 00000000000..d4cba14414c
--- /dev/null
+++ b/progs/trivial/vbo-tri.c
@@ -0,0 +1,131 @@
+/* Even simpler for many drivers than trivial/tri -- pass-through
+ * vertex shader and vertex data in a VBO.
+ */
+
+#include <assert.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <GL/glew.h>
+#include <GL/glut.h>
+
+
+struct {
+   GLfloat pos[4];
+   GLfloat color[4];
+} verts[] =  
+{
+   { {  -0.9, -0.9, 0.0, 1.0 },
+     {.8,0,0, 1}, 
+   },
+
+   { {  0.9,  -0.9, 0.0, 1.0 },
+     { 0, .9, 0, 1 },
+   },
+
+   { { 0,  0.9, 0.0, 1.0 },
+     {0,0,.7, 1}, 
+   },
+};
+
+GLuint arrayObj;
+
+static void Init( void )
+{
+   GLint errno;
+   GLuint prognum;
+   
+   static const char *prog1 =
+      "!!ARBvp1.0\n"
+      "MOV  result.color, vertex.color;\n"
+      "MOV  result.position, vertex.position;\n"
+      "END\n";
+
+
+   glGenProgramsARB(1, &prognum);
+
+   glBindProgramARB(GL_VERTEX_PROGRAM_ARB, prognum);
+   glProgramStringARB(GL_VERTEX_PROGRAM_ARB, GL_PROGRAM_FORMAT_ASCII_ARB,
+		      strlen(prog1), (const GLubyte *) prog1);
+
+   assert(glIsProgramARB(prognum));
+   errno = glGetError();
+   printf("glGetError = %d\n", errno);
+   if (errno != GL_NO_ERROR)
+   {
+      GLint errorpos;
+
+      glGetIntegerv(GL_PROGRAM_ERROR_POSITION_ARB, &errorpos);
+      printf("errorpos: %d\n", errorpos);
+      printf("%s\n", (char *)glGetString(GL_PROGRAM_ERROR_STRING_ARB));
+   }
+
+
+   glEnableClientState( GL_VERTEX_ARRAY );
+   glEnableClientState( GL_COLOR_ARRAY );
+
+   glGenBuffersARB(1, &arrayObj);
+   glBindBufferARB(GL_ARRAY_BUFFER_ARB, arrayObj);
+   glBufferDataARB(GL_ARRAY_BUFFER_ARB, sizeof(verts), verts, GL_STATIC_DRAW_ARB);
+
+   glVertexPointer( 4, GL_FLOAT, sizeof(verts[0]), 0 );
+   glColorPointer( 4, GL_FLOAT, sizeof(verts[0]), (void *)(4*sizeof(float)) );
+}
+
+
+
+static void Display( void )
+{
+   glClearColor(0.3, 0.3, 0.3, 1);
+   glClear( GL_COLOR_BUFFER_BIT );
+
+   glEnable(GL_VERTEX_PROGRAM_NV);
+   glDrawArrays( GL_TRIANGLES, 0, 3 );
+
+   glutSwapBuffers();
+}
+
+
+static void Reshape( int width, int height )
+{
+   glViewport( 0, 0, width, height );
+   glMatrixMode( GL_PROJECTION );
+   glLoadIdentity();
+   glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
+   glMatrixMode( GL_MODELVIEW );
+   glLoadIdentity();
+   /*glTranslatef( 0.0, 0.0, -15.0 );*/
+}
+
+
+static void Key( unsigned char key, int x, int y )
+{
+   (void) x;
+   (void) y;
+   switch (key) {
+      case 27:
+         exit(0);
+         break;
+   }
+   glutPostRedisplay();
+}
+
+
+
+
+int main( int argc, char *argv[] )
+{
+   glutInit( &argc, argv );
+   glutInitWindowPosition( 0, 0 );
+   glutInitWindowSize( 250, 250 );
+   glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE );
+   glutCreateWindow(argv[0]);
+   glewInit();
+   glutReshapeFunc( Reshape );
+   glutKeyboardFunc( Key );
+   glutDisplayFunc( Display );
+   Init();
+   glutMainLoop();
+   return 0;
+}
-- 
2.30.2