Make options documentation consistent

also resolve confusion between Y axis on image vs. in-game

README.rst

@@ -4,16 +4,18 @@ Minetest Mapper C++
 .. image:: https://github.com/minetest/minetestmapper/workflows/build/badge.svg
     :target: https://github.com/minetest/minetestmapper/actions/workflows/build.yml
 
-Minetestmapper generates an overview image from a Luanti map.
+Minetestmapper generates a top-down overview image from a Luanti map.
 
 A port of minetestmapper.py to C++ from `the obsolete Python script
 <https://github.com/minetest/minetest/tree/0.4.17/util>`_.
 This version is both faster and provides more features.
 
-Minetestmapper ships with a colors.txt file for Minetest Game, if you use a different game or have
-many mods installed you should generate a matching colors.txt for better results.
+Minetestmapper ships with a colors.txt file suitable for Minetest Game,
+if you use a different game or have mods installed you should generate a
+matching colors.txt for better results (colors will be missing otherwise).
 The `generate_colorstxt.py script 
-<./util/generate_colorstxt.py>`_ in the util folder exists for this purpose, detailed instructions can be found within.
+<./util/generate_colorstxt.py>`_ in the util folder exists for this purpose,
+detailed instructions can be found within.
 
 Requirements
 ------------
@@ -41,7 +43,8 @@ Minetestmapper for Windows can be downloaded `from the Releases section
 <https://github.com/minetest/minetestmapper/releases>`_.
 
 After extracting the archive, it can be invoked from cmd.exe or PowerShell:
-::
+
+.. code-block:: dos
 
 	cd C:\Users\yourname\Desktop\example\path
 	minetestmapper.exe --help
@@ -49,7 +52,7 @@ After extracting the archive, it can be invoked from cmd.exe or PowerShell:
 Compilation
 -----------
 
-::
+.. code-block:: bash
 
     cmake . -DENABLE_LEVELDB=1
     make -j$(nproc)
@@ -57,8 +60,8 @@ Compilation
 Usage
 -----
 
-`minetestmapper` has two mandatory paremeters, `-i` (input world path)
-and `-o` (output image path).
+``minetestmapper`` has two mandatory paremeters, ``-i`` (input world path)
+and ``-o`` (output image path).
 
 ::
 
@@ -90,7 +93,7 @@ draworigin:
     Draw origin indicator, ``--draworigin``
 
 drawalpha:
-    Allow nodes to be drawn with transparency (e.g. water), ``--drawalpha``
+    Allow nodes to be drawn with transparency (such as water), ``--drawalpha``
 
 extent:
     Don't output any imagery, just print the extent of the full map, ``--extent``
@@ -101,11 +104,14 @@ noshading:
 noemptyimage:
     Don't output anything when the image would be empty, ``--noemptyimage``
 
+verbose:
+    Enable verbose log putput, ``--verbose``
+
 min-y:
-    Don't draw nodes below this y value, e.g. ``--min-y -25``
+    Don't draw nodes below this Y value, e.g. ``--min-y -25``
 
 max-y:
-    Don't draw nodes above this y value, e.g. ``--max-y 75``
+    Don't draw nodes above this Y value, e.g. ``--max-y 75``
 
 backend:
     Override auto-detected map backend; supported: *sqlite3*, *leveldb*, *redis*, *postgresql*, e.g. ``--backend leveldb``
@@ -113,8 +119,10 @@ backend:
 geometry:
     Limit area to specific geometry (*x:z+w+h* where x and z specify the lower left corner), e.g. ``--geometry -800:-800+1600+1600``
 
+    The coordinates are specified with the same axes as in-game. The Z axis becomes Y when projected on the image.
+
 zoom:
-    Apply zoom to drawn nodes by enlarging them to n*n squares, e.g. ``--zoom 4``
+    Zoom the image by using more than one pixel per node, e.g. ``--zoom 4``
 
 colors:
     Override auto-detected path to colors.txt, e.g. ``--colors ../world/mycolors.txt``
@@ -123,6 +131,9 @@ scales:
     Draw scales on specified image edges (letters *t b l r* meaning top, bottom, left and right), e.g. ``--scales tbr``
 
 exhaustive:
-    | Select if database should be traversed exhaustively or using range queries, available: *never*, *y*, *full*, *auto*
-    | Defaults to *auto*. You shouldn't need to change this, but doing so can improve rendering times on large maps.
-    | For these optimizations to work it is important that you set ``min-y`` and ``max-y`` when you don't care about the world below e.g. -60 and above 1000 nodes.
+    Select if database should be traversed exhaustively or using range queries, available: *never*, *y*, *full*, *auto*
+
+    Defaults to *auto*. You shouldn't need to change this, as minetestmapper tries to automatically picks the best option.
+
+dumpblock:
+    Instead of rendering anything try to load the block at the given position (*x,y,z*) and print its raw data as hexadecimal.