Fast vertical pan on World page.

[#24] Capital W and S keys now apply fast vertical pan on World page.

3 files changed, 21 insertions, 6 deletions

diff --git a/bin/README.md b/bin/README.md
index ec6ff17..0d95d18 100644
--- a/bin/README.md
+++ b/bin/README.md
@@ -19,6 +19,7 @@ $ ./bin/salis.py load --file 16.sim
 |Left/Right arrow |Previous/next page |
 |Up/Down arrows   |Scroll page up/down if it can't fit terminal |
 |`wasd`           |Scroll/pan (PROCESS and WORLD page) |
+|`WS`             |Fast vertical scroll (PROCESS and WORLD page) |
 |`Q`              |Scroll to top (PROCESS and WORLD page) |
 |`A`              |Scroll to left (PROCESS page) |
 |`zx`             |Zoom in/out (WORLD page) |
diff --git a/bin/handler.py b/bin/handler.py
index 9c8ffaf..2bc8c25 100644
--- a/bin/handler.py
+++ b/bin/handler.py
@@ -70,8 +70,10 @@ class Handler:
 			self.__printer.world.pan_up()
 			self.__printer.proc_scroll_up()
 		elif cmd == ord("S"):
+			self.__printer.world.pan_down(fast=True)
 			self.__printer.proc_scroll_down(fast=True)
 		elif cmd == ord("W"):
+			self.__printer.world.pan_up(fast=True)
 			self.__printer.proc_scroll_up(fast=True)
 		elif cmd == ord("Q"):
 			self.__printer.world.pan_reset()
diff --git a/bin/world.py b/bin/world.py
index 31674f2..08f2734 100644
--- a/bin/world.py
+++ b/bin/world.py
@@ -113,18 +113,25 @@ class World:
 			max_pos = self.__sim.lib.sal_mem_get_size() - 1
 			self.pos = min(self.pos + self.zoom, max_pos)
 
-	def pan_down(self):
-		""" Pan world downward (pos += zoom * columns).
+	def pan_down(self, fast=False):
+		""" Pan world downward.
 		"""
 		if self.__is_world_editable():
-			self.pos = max(self.pos - self.__get_line_area(), 0)
+			if fast:
+				self.pos = max(self.pos - self.__get_world_area(), 0)
+			else:
+				self.pos = max(self.pos - self.__get_line_area(), 0)
 
-	def pan_up(self):
-		""" Pan world upward (pos -= zoom * columns).
+	def pan_up(self, fast=False):
+		""" Pan world upward.
 		"""
 		if self.__is_world_editable():
 			max_pos = self.__sim.lib.sal_mem_get_size() - 1
-			self.pos = min(self.pos + self.__get_line_area(), max_pos)
+
+			if fast:
+				self.pos = min(self.pos + self.__get_world_area(), max_pos)
+			else:
+				self.pos = min(self.pos + self.__get_line_area(), max_pos)
 
 	def pan_reset(self):
 		""" Set world position to zero.
@@ -265,3 +272,8 @@ class World:
 		line_size = self.__printer.size[1] - self.PADDING
 		line_area = self.zoom * line_size
 		return line_area
+
+	def __get_world_area(self):
+		""" Return amount of bytes contained in the entire WORLD view.
+		"""
+		return self.__get_line_area() * self.__printer.size[0]