1 files changed, 78 insertions, 0 deletions
diff --git a/pysamples/load_block.py b/pysamples/load_block.py
new file mode 100644
index 0000000..a457504
--- /dev/null
+++ b/pysamples/load_block.py
@@ -0,0 +1,78 @@
+#Copyright (c) 2011, Walter Bender
+
+# This procedure is invoked when the user-definable block on the
+# "extras" palette is selected.
+
+# Usage: Import this code into a Python (user-definable) block; when
+# this code is run, the turtle will create a block at the current
+# location of the turtle.  The first argument to the Python block
+# should be a string containing the name of the desired
+# block. Arguments to the block can be passed by expanding the Python
+# block to include up to two additional arguments.  Note that the
+# turtle is moved to the bottom of the block after it is loaded in
+# order position another block to the bottom of the stack.
+
+# For example, try the following to place forward 100, right 90 on the canvas:
+# start
+# Python(forward, 100)  <-- Python load_block.py expanded to two arguments
+# Python(right, 90)  <-- Python load_block.py expanded to two arguments
+
+
+def myblock(tw, blkname):
+    ''' Load a block on to the canvas '''
+
+    from TurtleArt.tapalette import block_names, block_primitives, \
+        special_names, content_blocks
+    from TurtleArt.tautils import find_group
+
+    def make_block(tw, name, x, y, defaults):
+        x_pos = x + 20
+        y_pos = y + 20
+        tw._new_block(name, x_pos, y_pos, defaults)
+
+        # Find the block we just created and attach it to a stack.
+        tw.drag_group = None
+        spr = tw.sprite_list.find_sprite((x_pos, y_pos))
+        if spr is not None:
+            blk = tw.block_list.spr_to_block(spr)
+            if blk is not None:
+                tw.drag_group = find_group(blk)
+                tw._snap_to_dock()
+
+        # Disassociate new block from mouse.
+        tw.drag_group = None
+        return blk.height
+
+    def find_block(tw, blkname, x, y, defaults=None):
+        """ Create a new block. It is a bit more work than just calling
+        _new_block(). We need to:
+        (1) translate the label name into the internal block name;
+        (2) 'dock' the block onto a stack where appropriate; and
+        (3) disassociate the new block from the mouse. """
+
+        print blkname
+        for name in block_names:
+            # Translate label name into block/prim name.
+            if blkname in block_names[name]:
+                if (name in block_primitives and \
+                        block_primitives[name] == name) or \
+                        name in content_blocks:
+                    return make_block(tw, name, x, y, defaults)
+        for name in special_names:
+            # Translate label name into block/prim name.
+            if blkname in special_names[name]:
+                return make_block(tw, name, x, y, defaults)
+        return -1
+
+    # Place the block at the active turtle (x, y) and move the turtle
+    # into position to place the next block in the stack.
+    x, y = tw.active_turtle.get_xy()
+    if type(blkname) == type([]):
+        name = blkname[0]
+        value = blkname[1:]
+        dy = int(find_block(tw, name, x, y, value))
+    else:
+        name = blkname
+        dy = int(find_block(tw, name, x, y))
+
+    tw.active_turtle.move((x, y - dy))