diff --git a/panda/src/tinydisplay/tinyXGraphicsWindow.cxx b/panda/src/tinydisplay/tinyXGraphicsWindow.cxx
index ba0f50fb67..1c3b594849 100644
--- a/panda/src/tinydisplay/tinyXGraphicsWindow.cxx
+++ b/panda/src/tinydisplay/tinyXGraphicsWindow.cxx
@@ -223,7 +223,7 @@ begin_flip() {
   }
 
   XPutImage(_display, _xwindow, _gc, _ximage, 0, 0, 0, 0,
-            _properties.get_x_size(), _properties.get_y_size());
+            _frame_buffer->xsize, _frame_buffer->ysize);
   XFlush(_display);
 }
 
@@ -316,7 +316,7 @@ process_events() {
         properties.set_size(event.xconfigure.width, event.xconfigure.height);
         system_changed_properties(properties);
         ZB_resize(_frame_buffer, NULL, _properties.get_x_size(), _properties.get_y_size());
-        _pitch = _properties.get_x_size() * _bytes_per_pixel;
+        _pitch = (_frame_buffer->xsize * _bytes_per_pixel + 3) & ~3;
         create_ximage();
       }
       break;
@@ -1588,7 +1588,7 @@ create_frame_buffer() {
   }
 
   _frame_buffer = ZB_open(_properties.get_x_size(), _properties.get_y_size(), mode, 0, 0, 0, 0);
-  _pitch = _properties.get_x_size() * _bytes_per_pixel;
+  _pitch = (_frame_buffer->xsize * _bytes_per_pixel + 3) & ~3;
 }
 
 
@@ -1609,15 +1609,15 @@ create_ximage() {
     _ximage = NULL;
   }
 
-  int image_size = _properties.get_x_size() * _properties.get_y_size() * _bytes_per_pixel;
+  int image_size = _frame_buffer->ysize * _pitch;
   char *data = NULL;
   if (_bytes_per_pixel != 4) {
     data = (char *)PANDA_MALLOC_ARRAY(image_size);
   }
 
   _ximage = XCreateImage(_display, _visual, _depth, ZPixmap, 0, data,
-                         _properties.get_x_size(), _properties.get_y_size(),
-                         8, 0);
+                         _frame_buffer->xsize, _frame_buffer->ysize,
+                         32, 0);
 }
 
 #endif  // IS_LINUX
diff --git a/panda/src/tinydisplay/zbuffer.c b/panda/src/tinydisplay/zbuffer.c
index 2b74e92546..b2c80592b9 100644
--- a/panda/src/tinydisplay/zbuffer.c
+++ b/panda/src/tinydisplay/zbuffer.c
@@ -22,6 +22,9 @@ ZBuffer *ZB_open(int xsize, int ysize, int mode,
     if (zb == NULL)
 	return NULL;
 
+    /* xsize must be a multiple of 4 */
+    xsize = xsize & ~3;
+
     zb->xsize = xsize;
     zb->ysize = ysize;
     zb->mode = mode;
@@ -98,7 +101,6 @@ void ZB_resize(ZBuffer * zb, void *frame_buffer, int xsize, int ysize)
     zb->linesize = (xsize * PSZB + 3) & ~3;
 
     size = zb->xsize * zb->ysize * sizeof(unsigned short);
-
     gl_free(zb->zbuf);
     zb->zbuf = gl_malloc(size);
 
@@ -331,7 +333,7 @@ void ZB_clear_viewport(ZBuffer * zb, int clear_z, int z,
   }
   if (clear_color) {
     color = RGBA_TO_PIXEL(r, g, b, a);
-    pp = zb->pbuf + xmin + ymin * zb->xsize;
+    pp = zb->pbuf + xmin + ymin * (zb->linesize / PSZB);
     for (y = 0; y < ysize; ++y) {
       memset_l(pp, color, xsize);
       pp += zb->xsize;