* version of glutdemo that uses vertex arrays instead of immediate mode

git-svn-id: http://svn.freepascal.org/svn/fpc/trunk@12481 3ad0048d-3df7-0310-abae-a5850022a9f2

2 files changed, 159 insertions, 1 deletions

diff --git a/packages/opengl/examples/Makefile.fpc b/packages/opengl/examples/Makefile.fpc
index 1ec11d8810..31c5102ce5 100644
--- a/packages/opengl/examples/Makefile.fpc
+++ b/packages/opengl/examples/Makefile.fpc
@@ -3,7 +3,7 @@
 #
 
 [target]
-programs=glutdemo morph3d bounce radblur
+programs=glutdemo morph3d bounce radblur glutdemova
 programs_linux=glxtest
 programs_freebsd=glxtest
 programs_netbsd=glxtest
diff --git a/packages/opengl/examples/glutdemova.pp b/packages/opengl/examples/glutdemova.pp
new file mode 100644
index 0000000000..49c6686a0c
--- /dev/null
+++ b/packages/opengl/examples/glutdemova.pp
@@ -0,0 +1,158 @@
+{
+  GL units for Free Pascal - GLUT demo
+  1999 Sebastian Guenther, sguenther@gmx.de
+  2008 Jonas Maebe (converted to use vertex arrays)
+
+  You may use this source as starting point for your own programs; consider it
+  as Public Domain.
+}
+
+{$mode objfpc}
+
+program GLUTDemoVA;
+uses
+  GL, GLU, GLUT;
+
+const
+
+  FPCImg: array[0..4, 0..10] of Byte =
+    ((1, 1, 1, 0, 1, 1, 1, 0, 0, 1, 1),
+     (1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0),
+     (1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 0),
+     (1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0),
+     (1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1));
+
+var
+  counter: Integer;
+
+(*
+    3 __ 2
+    /|  |
+  7/0|_ |1
+   |/  /
+   +--+
+   4  5
+
+back plane: 0-3-2-1
+*)
+
+const
+  colors: array[0..7, 0..2] of Single =
+    ((0, 0, 0), (0, 0, 1), (0, 1, 0), (0, 1, 1),
+     (1, 0, 0), (1, 0, 1), (1, 1, 0), (1, 1, 1));
+  corners: array[0..7, 0..2] of Single =
+    ((-1, -1, -1), (+1, -1, -1), (+1, +1, -1), (-1, +1, -1),
+     (-1, -1, +1), (+1, -1, +1), (+1, +1, +1), (-1, +1, +1));
+
+  indices: array[0..5] of array[0..3] of GLubyte =
+    (
+     { all vertices must be in ccw order }
+     (0,3,1,2), // back
+     (4,5,7,6), // front
+     (3,0,7,4), // left
+     (1,2,5,6), // right
+     (3,7,2,6), // top
+     (5,4,1,0)  // bottom
+    );
+
+procedure DrawCube;
+begin
+  glEnableClientState(GL_VERTEX_ARRAY);
+  glEnableClientState(GL_COLOR_ARRAY);
+
+  glVertexPointer(3,GL_FLOAT,0,@corners);
+  glColorPointer(3,GL_FLOAT,0,@colors);
+
+  // this will also draw a bunch of triangles inside the cube, but
+  // may still be faster than the commented-out sequence below due
+  // to less calls into the renderer
+  glDrawElements(GL_TRIANGLE_STRIP,24,GL_UNSIGNED_BYTE,@indices[0]);
+
+(*
+  glDrawElements(GL_TRIANGLE_STRIP,4,GL_UNSIGNED_BYTE,@indices[0]);
+  glDrawElements(GL_TRIANGLE_STRIP,4,GL_UNSIGNED_BYTE,@indices[1]);
+  glDrawElements(GL_TRIANGLE_STRIP,4,GL_UNSIGNED_BYTE,@indices[2]);
+  glDrawElements(GL_TRIANGLE_STRIP,4,GL_UNSIGNED_BYTE,@indices[3]);
+  glDrawElements(GL_TRIANGLE_STRIP,4,GL_UNSIGNED_BYTE,@indices[4]);
+  glDrawElements(GL_TRIANGLE_STRIP,4,GL_UNSIGNED_BYTE,@indices[5]);
+*)
+  glDisableClientState(GL_VERTEX_ARRAY);
+  glDisableClientState(GL_COLOR_ARRAY);
+end;
+
+
+procedure DisplayWindow; cdecl;
+var
+  x, y: Integer;
+begin
+  Inc(counter);
+
+//  counter:=145;
+  glClearColor(0, 0, 0.2, 1);
+  glClear(GL_COLOR_BUFFER_BIT+GL_DEPTH_BUFFER_BIT);
+
+  glPushMatrix;
+  glTranslatef(0, 0, Sin(Single(counter) / 20.0) * 5.0 - 5.0);
+  glRotatef(Sin(Single(counter) / 200.0) * 720.0, 0, 1, 0);
+  glRotatef(counter, 0, 0, 1);
+
+  for y := 0 to 4 do
+    for x := 0 to 10 do
+      if FPCImg[y, x] > 0 then begin
+        glPushMatrix;
+        glRotatef(x * Sin(Single(counter) / 5.0), 0, 1, 0);
+        glRotatef(y * Sin(Single(counter) / 12.0) * 4.0, 0, 0, 1);
+        glTranslatef((x - 5) * 1, (2 - y) * 1, 0);
+        glScalef(0.4, 0.4, 0.4);
+        glRotatef(counter, 0.5, 1, 0);
+        DrawCube;
+        glPopMatrix;
+      end;
+
+  glPopMatrix;
+
+//  Inc(counter);
+
+  glutSwapBuffers;
+end;
+
+procedure OnTimer(value: Integer); cdecl;
+begin
+  glutPostRedisplay;
+  glutTimerFunc(20, @OnTimer, 0);
+end;
+
+begin
+  glutInit(@argc, argv);
+
+  glutInitDisplayMode(GLUT_RGB or GLUT_DOUBLE or GLUT_DEPTH);
+  glutCreateWindow('Free Pascal GLUT demo');
+  glutDisplayFunc(@DisplayWindow);
+  glutTimerFunc(20, @OnTimer, 0);
+
+  WriteLn;
+  WriteLn('GL info:');
+  WriteLn('  Vendor: ', PChar(glGetString(GL_VENDOR)));
+  WriteLn('  Renderer: ', PChar(glGetString(GL_RENDERER)));
+  WriteLn('  Version: ', PChar(glGetString(GL_VERSION)));
+  WriteLn('  Extensions: ', PChar(glGetString(GL_EXTENSIONS)));
+
+  // Enable backface culling
+  glEnable(GL_CULL_FACE);
+
+  // Set up depth buffer
+  glEnable(GL_DEPTH_TEST);
+  glDepthFunc(GL_LESS);
+
+  // Set up projection matrix
+  glMatrixMode(GL_PROJECTION);
+  glLoadIdentity;
+  gluPerspective(90, 1.3, 0.1, 100);
+  glMatrixMode(GL_MODELVIEW);
+  glLoadIdentity;
+  glTranslatef(0, 0, -5.5);
+
+  WriteLn('Starting...');
+  glutMainLoop;
+
+end.