now lines are drawn for the example, first steps to make clients independent.

1 files changed, 87 insertions, 24 deletions

diff --git a/example.c b/example.c
index 2fe1d3f..22d1c04 100644
--- a/example.c
+++ b/example.c
@@ -32,36 +32,92 @@
 
 const int maxx=640, maxy=480, bpp=4;
 
-void initBuffer(char* buffer)
+/* This initializes a nice (?) background */
+
+void initBuffer(unsigned char* buffer)
 {
   int i,j;
   for(i=0;i<maxx;++i)
     for(j=0;j<maxy;++j) {
-      buffer[(j*maxx+i)*bpp]=i*256/maxx;
-      buffer[(j*maxx+i)*bpp+1]=j*256/maxy;
-      buffer[(j*maxx+i)*bpp+2]=(i+j)*256/(maxx*maxy);
-      buffer[(j*maxx+i)*bpp+3]=(i-j)*256/(maxx*maxy);
+      buffer[(j*maxx+i)*bpp+1]=(i+j)*256/(maxx+maxy); /* red */
+      buffer[(j*maxx+i)*bpp+2]=i*256/maxx; /* green */
+      buffer[(j*maxx+i)*bpp+3]=j*256/maxy; /* blue */
     }
 }
 
+/* Here we create a structure so that every client has it's own pointer */
+
+typedef struct ClientData {
+  Bool oldButton;
+  int oldx,oldy;
+} ClientData;
+
+void clientgone(rfbClientPtr cl)
+{
+  free(cl->clientData);
+}
+
+void newclient(rfbClientPtr cl)
+{
+  cl->clientData = (void*)calloc(sizeof(ClientData),1);
+  cl->clientGoneHook = clientgone;
+}
+
+/* aux function to draw a line */
+void drawline(unsigned char* buffer,int rowstride,int bpp,int x1,int y1,int x2,int y2)
+{
+  int i,j;
+  i=x1-x2; j=y1-y2;
+  if(i<0) i=-i;
+  if(j<0) j=-j;
+  if(i<j) {
+    if(y1>y2) { i=y2; y2=y1; y1=i; i=x2; x2=x1; x1=i; }
+    if(y2==y1) { if(y2>0) y1--; else y2++; }
+    for(j=y1;j<=y2;j++)
+      for(i=0;i<bpp;i++)
+	buffer[j*rowstride+(x1+(j-y1)*(x2-x1)/(y2-y1))*bpp+i]=0xff;
+  } else {
+    if(x1>x2) { i=y2; y2=y1; y1=i; i=x2; x2=x1; x1=i; }
+    for(i=x1;i<=x2;i++)
+      for(j=0;j<bpp;j++)
+	buffer[(y1+(i-x1)*(y2-y1)/(x2-x1))*rowstride+i*bpp+j]=0xff;
+  }
+}
+    
+/* Here the pointer events are handled */
+
 void doptr(int buttonMask,int x,int y,rfbClientPtr cl)
 {
+   ClientData* cd=cl->clientData;
    if(buttonMask && x>=0 && y>=0 && x<maxx && y<maxy) {
       int i,j,x1,x2,y1,y2;
-      x1=x-buttonMask; if(x1<0) x1=0;
-      x2=x+buttonMask; if(x2>maxx) x2=maxx;
-      y1=y-buttonMask; if(y1<0) y1=0;
-      y2=y+buttonMask; if(y2>maxy) y2=maxy;
-
-      for(i=x1*bpp;i<x2*bpp;i++)
-	for(j=y1;j<y2;j++)
-	  cl->screen->frameBuffer[j*cl->screen->paddedWidthInBytes+i]=0xff;
-      rfbMarkRectAsModified(cl->screen,x1,y1,x2,y2);
-      rfbGotXCutText(cl->screen,"Hallo",5);
-   }
-}
 
+      if(cd->oldButton==buttonMask) { /* draw a line */
+	drawline(cl->screen->frameBuffer,cl->screen->paddedWidthInBytes,bpp,
+		 x,y,cd->oldx,cd->oldy);
+	rfbMarkRectAsModified(cl->screen,x,y,cd->oldx,cd->oldy);
+      } else { /* draw a point (diameter depends on button) */
+	x1=x-buttonMask; if(x1<0) x1=0;
+	x2=x+buttonMask; if(x2>maxx) x2=maxx;
+	y1=y-buttonMask; if(y1<0) y1=0;
+	y2=y+buttonMask; if(y2>maxy) y2=maxy;
+
+	for(i=x1*bpp;i<x2*bpp;i++)
+	  for(j=y1;j<y2;j++)
+	    cl->screen->frameBuffer[j*cl->screen->paddedWidthInBytes+i]=0xff;
+	rfbMarkRectAsModified(cl->screen,x1,y1,x2-1,y2-1);
+      }
 
+      /* we could get a selection like that:
+	 rfbGotXCutText(cl->screen,"Hallo",5);
+      */
+
+      cd->oldx=x; cd->oldy=y; cd->oldButton=buttonMask;
+   } else
+     cd->oldButton=0;
+}
+
+/* Here the key events are handled */
 
 void dokey(Bool down,KeySym key,rfbClientPtr cl)
 {
@@ -73,21 +129,28 @@ void dokey(Bool down,KeySym key,rfbClientPtr cl)
   }
 }
 
+/* Initialisation */
+
 int main(int argc,char** argv)
 {
-  rfbScreenInfoPtr rfbScreen = rfbDefaultScreenInit(argc,argv);
-  rfbScreen->desktopName="LibVNCServer Example";
+  rfbScreenInfoPtr rfbScreen =
+    rfbDefaultScreenInit(argc,argv,maxx,maxy,8,3,bpp);
+  rfbScreen->desktopName = "LibVNCServer Example";
   rfbScreen->frameBuffer = (char*)malloc(maxx*maxy*bpp);
-  rfbScreen->width=maxx;
-  rfbScreen->height=maxy;
-  rfbScreen->paddedWidthInBytes=maxx*bpp;
-  rfbScreen->ptrAddEvent=doptr;
-  rfbScreen->kbdAddEvent=dokey;
+  rfbScreen->rfbAlwaysShared = TRUE;
+  rfbScreen->ptrAddEvent = doptr;
+  rfbScreen->kbdAddEvent = dokey;
+  rfbScreen->newClientHook = newclient;
 
   initBuffer(rfbScreen->frameBuffer);
 
+  /* this is the blocking event loop, i.e. it never returns */
   runEventLoop(rfbScreen,40000,FALSE);
+
+  /* this is the non-blocking event loop; a background thread is started */
   runEventLoop(rfbScreen,40000,TRUE);
+
+  /* now we could do some cool things like rendering */
   while(1);
    
   return(0);