Collision

4 files changed, 15 insertions, 43 deletions

diff --git a/Add-a-new-tileset.md b/Add-a-new-tileset.md
index 9237881..0f1d451 100644
--- a/Add-a-new-tileset.md
+++ b/Add-a-new-tileset.md
@@ -8,10 +8,9 @@ This tutorial is for how to add a new tileset. As an example, we'll add Pewter M
 3. [Design its graphics](#3-design-its-graphics)
 4. [Design its palette map](#4-design-its-palette-map)
 5. [Design its blocks (aka metatiles)](#5-design-its-blocks-aka-metatiles)
-6. [Define its collision data](#6-define-its-collision-data)
-7. [Include the new files in the ROM](#7-include-the-new-files-in-the-rom)
-8. [Define its animated tiles](#8-define-its-animated-tiles)
-9. [Design a custom palette for it](#9-design-a-custom-palette-for-it)
+6. [Include the new files in the ROM](#6-include-the-new-files-in-the-rom)
+7. [Define its animated tiles](#7-define-its-animated-tiles)
+8. [Design a custom palette for it](#8-design-a-custom-palette-for-it)
 
 
 ## 1. Define a tileset constant
@@ -123,16 +122,22 @@ The `rept 16 \ db $ff \ endr` in the middle is skipping over tile IDs $60 to $7F
 
 ## 5. Design its blocks (aka metatiles)
 
-Maps in pokecrystal are designed with blocks, not tiles, where each block (aka "metatile") is a 4x4 square of tiles.
+Maps in pokecrystal are designed with blocks, not tiles, where each block (aka "metatile") is a 4x4 square of tiles. Each block also has 2x2 "collision" data describing how NPCs can interact with each quadrant.
 
 Download [gfx/blocksets/gate.bst](https://github.com/pret/pokered/blob/master/gfx/blocksets/gate.bst) from pokered and save it as **data/tilesets/museum_metatiles.bin**. (Yes, the formats are identical from Gen 1 to Gen 2.)
 
-If this were an original tileset, you would have to create the file. You can create an empty text file with the extension .bin instead of .txt, or run the command `touch data/tilesets/museum_metatiles.bin` the same way you run `make`. Either way, you'd still have to define the blocks. You can technically design blocks with a hex editor, typing in tile IDs one by one, but that's tedious.
+If this were an original tileset, you would have to create the file. You can create an empty text file with the extension .bin instead of .txt, or run the command `touch data/tilesets/museum_metatiles.bin` the same way you run `make`.
 
-Instead, you can use [Polished Map](https://github.com/Rangi42/polished-map). It's a program for editing maps and tilesets. Just open any of the [maps/\*.blk](../tree/master/maps/) files and pick "museum" as its tileset. As long as the graphics, palette map, and metatiles.bin files exist, this will work. Then click Tools → Resize Blockset… (or the blue **±** button) to add some blocks to the sidebar, and right-click one of them to open the block editor:
+Then create **data/tilesets/museum_collision.asm**. This should also be an empty file. (The collision system in pokered was very different from pokecrystal, based on tiles instead of blocks, so we can't copy it this time.)
+
+At this point, you *could* design the blocks one by one, using a text editor for museum_collision.asm and a hex editor for museum_metatiles.bin. But that's tedious and error-prone.
+
+Instead, you can use [Polished Map](https://github.com/Rangi42/polished-map). It's a program for editing maps and tilesets. Just open any of the [maps/\*.blk](../tree/master/maps/) files and pick "museum" as its tileset. As long as the graphics, palette map, metatiles, and collision files exist, this will work. Then click Tools → Resize Blockset… (or the blue **±** button) to add some blocks to the sidebar, and right-click one of them to open the block editor:
 
 ![Screenshot](screenshots/polished-map-edit-block.png)
 
+Just place the tiles and type the collision values for each block. Tiles are selected from the tileset, and valid collision values are in [constants/collision_constants.asm](../blob/master/constants/collision_constants.asm).
+
 You can also edit the tileset graphics and palette map from within Polished Map. Just click Tools → Edit Tileset… (or the green puzzle piece button):
 
 ![Screenshot](screenshots/polished-map-edit-tile.png)
@@ -148,40 +153,7 @@ Here, I downloaded [maps/museum1f.blk](https://github.com/pret/pokered/blob/mast
 Then I swapped block #0 (floor) and block #10 (solid black) and saved that change, so the border block would be #0 and the floor would be walkable.
 
 
-## 6. Define its collision data
-
-Blocks are four times the size of NPCs. That means each block needs four pieces of collision data, defining how NPCs interact with the top-left, top-right, bottom-left, and bottom-right quadrants.
-
-Create **data/tilesets/museum_collision.asm**. As you can see from other collision data files, each block will need a `tilecoll` line defining the four quadrants. Valid collision values are in [constants/collision_constants.asm](../blob/master/constants/collision_constants.asm).
-
-The collision system in pokered was very different from pokecrystal, based on tiles instead of blocks, so we can't copy it this time. Here's a sample of valid collision data for the museum tileset:
-
-```diff
-+	tilecoll WALL, WALL, WALL, WALL ; 00
-+	tilecoll FLOOR, WALL, FLOOR, WALL ; 01
-+	tilecoll WALL, FLOOR, WALL, FLOOR ; 02
-+	tilecoll WALL, WALL, FLOOR, FLOOR ; 03
-+	tilecoll FLOOR, FLOOR, FLOOR, FLOOR ; 04
-+	tilecoll LADDER, FLOOR, FLOOR, FLOOR ; 05
-+	tilecoll WALL, WALL, WALL, FLOOR ; 06
-+	tilecoll WALL, WALL, FLOOR, WALL ; 07
-+	tilecoll FLOOR, COUNTER, FLOOR, COUNTER ; 08
-+	tilecoll COUNTER, FLOOR, COUNTER, FLOOR ; 09
-+	tilecoll FLOOR, FLOOR, FLOOR, FLOOR ; 0a
-+	tilecoll FLOOR, FLOOR, WARP_CARPET_DOWN, WARP_CARPET_DOWN ; 0b
-+	tilecoll FLOOR, COUNTER, WARP_CARPET_DOWN, FLOOR ; 0c
-+	tilecoll COUNTER, WALL, FLOOR, WALL ; 0d
-+	tilecoll WALL, COUNTER, WALL, FLOOR ; 0e
-+	tilecoll COUNTER, FLOOR, FLOOR, WARP_CARPET_DOWN ; 0f
-+	...
-```
-
-You'll have to define the other 112 blocks yourself. ;)
-
-As of version 3.4.0, Polished Map can edit collision data, so you can create an empty data/tilesets/museum_collision.asm file and then enter collision values at the same time as you're designing blocks in the previous step.
-
-
-## 7. Include the new files in the ROM
+## 6. Include the new files in the ROM
 
 Edit [gfx/tilesets.asm](../blob/master/gfx/tilesets.asm):
 
@@ -224,7 +196,7 @@ Now edit [gfx/tileset_palette_maps.asm](../blob/master/gfx/tileset_palette_maps.
 These files all go in the same section, so you can't have *too* many tilesets or the bank will overflow. That's unlikely to happen, but if it does, remember that most of the tilesets have excess palette data that can be removed.
 
 
-## 8. Define its animated tiles
+## 7. Define its animated tiles
 
 Edit [engine/tilesets/tileset_anims.asm](../blob/master/engine/tilesets/tileset_anims.asm):
 
@@ -249,7 +221,7 @@ Anyway, that's it. Now maps can use `TILESET_MUSEUM` like any other tileset.
 ![Screenshot](screenshots/museum-tileset.png)
 
 
-## 9. Design a custom palette for it
+## 8. Design a custom palette for it
 
 A few tilesets in pokecrystal have custom palettes. For example, Ice Path uses an entirely different palette from most caves; and Radio Tower uses a subtly different palette that makes `YELLOW` look green and `GREEN` look green-on-blue, so the tops of potted plants look natural against the blue walls.
 
diff --git a/screenshots/polished-map-edit-block.png b/screenshots/polished-map-edit-block.png
index 63f65cf..b03166d 100644
--- a/screenshots/polished-map-edit-block.png
+++ b/screenshots/polished-map-edit-block.png
diff --git a/screenshots/polished-map-pewter-museum.png b/screenshots/polished-map-pewter-museum.png
index 65cd757..abf440a 100644
--- a/screenshots/polished-map-pewter-museum.png
+++ b/screenshots/polished-map-pewter-museum.png
diff --git a/screenshots/polished-map-redplusplus-goldenrod-city.png b/screenshots/polished-map-redplusplus-goldenrod-city.png
index 6ef383f..4c733b6 100644
--- a/screenshots/polished-map-redplusplus-goldenrod-city.png
+++ b/screenshots/polished-map-redplusplus-goldenrod-city.png