Merge pull request #3 from tsoding/glxex

Glxex

.gitignore

@@ -1,3 +1,4 @@
 nimcache/
 boomer
-x11ex
+x11ex
+glxex

README.md

@@ -15,6 +15,7 @@ $ ./boomer
 
 - https://github.com/nim-lang/x11/blob/bf9dc74dd196a98b7c2a2beea4d92640734f7c60/examples/x11ex.nim
 - http://archive.xfce.org/src/xfce/xfwm4/4.13/
+- https://www.khronos.org/opengl/wiki/Programming_OpenGL_in_Linux:_GLX_and_Xlib
 
 ## Support
 

boomer.nimble

@@ -3,6 +3,6 @@ author      = "me"
 description = "Zoomer application for boomers"
 license     = "MIT"
 srcDir      = "src"
-bin         = @["boomer", "x11ex"]
+bin         = @["boomer", "x11ex", "glxex"]
 
-requires "nim >= 0.18.0", "x11 >= 1.1"
+requires "nim >= 0.18.0", "x11 >= 1.1", "opengl >= 1.2.3"

default.nix

@@ -6,7 +6,9 @@ with import <nixpkgs> {}; {
                         pkgconfig
                         nim
                         xorg.libX11
+                        libGL
+                        libGLU
                       ];
-        LD_LIBRARY_PATH="${xorg.libX11}/lib/";
+        LD_LIBRARY_PATH="/run/opengl-driver/lib;${xorg.libX11}/lib/;${libGL}/lib/;${libGLU}/lib";
     };
 }

src/glxex.nim

@@ -0,0 +1,111 @@
+import x11/xlib, x11/x
+import opengl, opengl/glx, opengl/glu
+
+proc DrawAQuad() = 
+  glClearColor(1.0, 1.0, 1.0, 1.0)
+  glClear(GL_COLOR_BUFFER_BIT or GL_DEPTH_BUFFER_BIT)
+ 
+  glMatrixMode(GL_PROJECTION)
+  glLoadIdentity()
+  glOrtho(-1.0, 1.0, -1.0, 1.0, 1.0, 20.0)
+ 
+  glMatrixMode(GL_MODELVIEW)
+  glLoadIdentity()
+  gluLookAt(0.0, 0.0, 10.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0)
+ 
+  glBegin(GL_QUADS)
+  glColor3f(1.0, 0.0, 0.0)
+  glVertex3f(-0.75, -0.75, 0.0)
+  glColor3f(0.0, 1.0, 0.0)
+  glVertex3f( 0.75, -0.75, 0.0)
+  glColor3f(0.0, 0.0, 1.0)
+  glVertex3f( 0.75,  0.75, 0.0)
+  glColor3f(1.0, 1.0, 0.0)
+  glVertex3f(-0.75,  0.75, 0.0)
+  glEnd()
+
+proc main() =
+  var display = XOpenDisplay(nil)
+  if display == nil:
+    quit "Failed to open display"
+  let screen = XDefaultScreen(display)
+
+  var glxMajor : int
+  var glxMinor : int
+
+  if (not glXQueryVersion(display, glxMajor, glxMinor) or
+      (glxMajor == 1 and glxMinor < 3) or
+      (glxMajor < 1)):
+    quit "Invalid GLX version. Expected >=1.3"
+  
+  echo("GLX version ", glxMajor, ".", glxMinor)
+
+  echo("GLX extension: ", $glXQueryExtensionsString(display, screen))
+
+  var att = [GLX_RGBA, GLX_DEPTH_SIZE, 24, GLX_DOUBLEBUFFER, None]
+
+  var root = DefaultRootWindow(display)
+  var vi = glXChooseVisual(display, 0, addr att[0])
+
+  if (vi == nil):
+    quit "No appropriate visual found"
+
+  echo("Visual ", vi.visualid, " selected")
+
+  var cmap = XCreateColormap(display, root, vi.visual, AllocNone)
+  var swa: TXSetWindowAttributes
+  swa.colormap = cmap
+  swa.event_mask = ExposureMask or KeyPressMask
+
+  var win = XCreateWindow(
+    display, root, 0, 0, 600, 600, 0,
+    vi.depth, InputOutput, vi.visual,
+    CWColormap or CWEventMask, addr swa)
+
+  discard XMapWindow(display, win)
+
+  discard XStoreName(display, win, "Wordpress Application")
+
+  var glc = glXCreateContext(display, vi, nil, GL_TRUE)
+
+  discard glXMakeCurrent(display, win, glc)
+
+  loadExtensions()
+
+  glEnable(GL_DEPTH_TEST)
+
+  var xev: TXEvent
+
+  glClearColor(0.0, 1.0, 0.0, 1.0)
+
+  while true:
+    var gwa: TXWindowAttributes
+    discard XGetWindowAttributes(display, win, addr gwa)
+    glViewport(0, 0, gwa.width, gwa.height)
+
+    glClear(GL_COLOR_BUFFER_BIT)
+
+    glMatrixMode(GL_PROJECTION)
+    glLoadIdentity()
+    glOrtho(-1.0, 1.0, -1.0, 1.0, 1.0, 20.0)
+
+    DrawAQuad()
+
+    glXSwapBuffers(display, win)
+
+    discard XNextEvent(display, addr xev)
+
+    case xev.theType
+    of Expose:
+      echo "hello"
+
+    of KeyPress:
+      discard glXMakeCurrent(display, None, nil)
+      glXDestroyContext(display, glc)
+      discard XDestroyWindow(display, win)
+      discard XCloseDisplay(display)
+      quit "done"
+    else:
+      discard
+
+main()