--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/R/rdyncall/demo/blink.R	Thu Mar 19 22:26:28 2015 +0100
@@ -0,0 +1,75 @@
+# Package: rdyncall 
+# File: demo/blink.R
+# Description: Simple SDL,OpenGL demonstration - a blinking screen
+
+dynport(SDL)
+dynport(GL)
+
+blink <- 0
+surface <- NULL
+
+init <- function()
+{
+  SDL_Init(SDL_INIT_VIDEO)
+  surface <<- SDL_SetVideoMode(640,480,32,SDL_OPENGL+SDL_DOUBLEBUF)
+  blink <<- 0
+}
+
+
+update <- function()
+{
+  glFinish()
+  glClearColor(0,0,blink,0)
+  glClear(GL_COLOR_BUFFER_BIT)
+  SDL_GL_SwapBuffers()
+  glFlush()
+  blink <<- ( blink + 0.01 ) %% 1
+}
+
+input <- function()
+{
+  return(TRUE)
+}
+
+checkGL <- function()
+{
+  glerror <- glGetError()
+  if (glerror != 0)
+  {
+    cat("GL Error", glerror, "\n")
+  }
+  return(glerror == 0)
+}
+
+mainloop <- function()
+{
+  sdlevent <- new.struct("SDL_Event")
+  quit <- FALSE
+  while(!quit)
+  {
+    update()
+    while( SDL_PollEvent(sdlevent) )
+    {
+      if (sdlevent$type == SDL_QUIT ) {
+        quit <- TRUE
+      } else if (sdlevent$type == SDL_MOUSEBUTTONDOWN) {
+        cat("button ", sdlevent$button$button ,"\n")
+      }
+    }
+    if ( !checkGL() ) quit <- TRUE
+  }
+}
+
+quit <- function()
+{
+  SDL_Quit()
+}
+
+run <- function()
+{  
+  init()
+  mainloop()
+  quit()
+}
+
+run()