minetest-birthstones/README.md

# Minetest Game mod: birthstones
(Based on birthstones Minetest mod by Doc22; textures based on CC-BY-SA work by various authors--
see LICENSE for full credits)

## Primary differences from original
### Main reasons for fork:
* add more tools
* make changes to code to make use of modern Minetest (such as ore drop string)

### Notable issues found in original (see items marked with '!' in "Changes" section for others):
(hopefully these changes get corrected there)
* birthstones were wrong month (see "birthstones list.csv" in etc folder for corrections, though month names are removed in fork)
* now stone_with_opal is generated now (was impossible to get by mining before, apparently)
* crafting block back to 9 gemstones is now possible
* found some code bugs (see exclamation points under "Changes" below)

### Other major differences from original
Some major changes were done to make the mod easier to maintain:
* changed to minetest_game's naming scheme for filenames and node/tool names (aliases added for backward compatibility)
* componentized into separate lua files for each category of operations


## Changes:
'!' is for bugs in 2012 version that are fixed (as opposed to features that were changed/added) in this fork
* (2017-02-16) Rerendered Alexandrite block&item; new textures for minerals: Alexandrite, Amethyst; collecting hd versions in etc/hd  
* (2017-02-16) blend file: completely reworked gem shader (blend version 2)
* (2017-02-15) blend file: connected ID Mask to Image output (in Compositor nodes) for alpha in rendered image
* (2017-02-13) Finished working gem and block textures for Topaz, Alexandrite, Amethyst, made in Blender by expertmm
* (2017-02-13) Made multi-sided Topaz Block (WIP) made in Blender
* (2017-02-13) Made Blender project for gem rendering (see Developer Notes below for usage)
* (2017-02-12) Add farming hoes
* (2017-02-11) Add recipe to create default:diamond from dye:blue + birthstones:diamond for playability (for when other mods like technic need diamonds for things)
* (2017-02-11) Add crafting recipe to convert block back into 9 gems
* (2017-02-11) Add Swords & Shovels
* (2017-02-11) Componentize into separate lua files for each category of operations
* !(2017-02-11) Make opal possible to get: added missing register_on_generated for changing some stone to opal (see oregen.lua)
* !(2017-02-11) Change drop for stone_with_topaz from stone_with_topaz to topaz (apparently this didn't cause an issue since craft method had been used)
* !(2017-02-11) Change drop of ores (to match modern style from default in minetest_game from minetest 0.4.15-git 2017-01), where * below is name:
```lua
	-- drop = 'craft "birthstones:*" 1',
	drop = "birthstones:*",
```
* !(2017-02-11) Block needs better pick to be mined: Changed groups:
```lua
	-- groups = {cracky = 3}
	groups = {cracky = 1, level = 3}
```
* !(2017-02-11) Ore needs better pick to be mined: changed groups.cracky of all from 3 to 1
* (2017-02-11) Changed "* Ore" to "Stone with *" (because why copy other people when you can make sense instead)
* !(2017-02-11) Preliminary step in fixing one-chop axes: changed register_tool time2 and time3 from:
	[1]=time1-2.0, [2]=2.0-time2, [3]=2.0-time3}
	to
	times={[1]=time1/2.0, [2]=time2/2.0, [3]=time3/2.0}
* !(2017-02-10) Removed month from display names to avoid breaking immersion (draws too much attention to the items having a "label")
	if re-added, months would have to be corrected anyway as follows (in the original mod, alphabetical order instead of actual birthstone month determined month):
	see etc/birthstones list.csv
* !(2017-02-10) Fixed issue where topaz ore was registered twice (didn't seem to cause problems)
* !(2017-02-10) Capitalized stone name when used within tool display name
* (2017-02-10) Naming changed to match minetest texture&variable naming scheme
```
    (see changes below, where ^* is capitalized mineral name and * is uncapitalized)
	(aliases added only for backward compatibility--see aliases.lua--doing aliases can be commented in init.lua)
	Files:
		^* TO birthstones_* (ITEM)
		^*_overlay TO birthstones_mineral_* (ORE OVERLAY)
		^*_block TO birthstones_*_block
		*_axe to birthstones_tool_*axe
		*_pick to birthstones_tool_*pick
		^*_block to birthstones_*_block
	Variables:
		birthstones:*ore TO birthstones:stone_with_*
		"birthstones:".. name .. "_pick" TO "birthstones:pick_"..name
		"birthstones:".. name .. "_axe" TO "birthstones:axe_"..name
```
* (2017-02-10) expertmm fork starting today

## Known Issues
* Improve block textures
* Make a trm for treasurer (separate mod)
* Make variables based on real hardness values (but allow all birthstones to break the same types of blocks, for playability):
  * #of uses, dig times, and fleshy damage group value now all based on real-life hardness values (see xlsx spreadsheet for details and sources and extrapolation formulas)
  * Formulas were determined using Excel:
    * Diamond theoretical Brinell explanation: Excel says the curve on 18carat.co.uk, if a power curve, is Brinell = 2.9592*(ans^2.2856) where ans is Moh value
    * Other extrapolated Brinell values (rounded to nearest whole number) explanation: Excel says power function for predicting from density is Brinell = 9.0954*(ans^2.9757) where ans is metric density value
    * Extrapolated Moh values explanation: Excel says power curve from 18carat.co.uk materials is: Moh = 0.6514*(ans^0.4269) where ans is Brinell value
(to use Speedcrunch to get values not listed, enter the number without any equation, then paste the formulas above exactly to use that "answer" as a variable--see spreadsheet's "Hardness - Extrapolated" sheet for spreadsheet version of formulas)

### Things that will be kept the same:
* You must manually delete the etc folder (source material) from your mods/birthtones folder to reduce download times of the mod when using a server
* birthstones:diamond will still be present for now (as opposed to becoming an alias for default:diamond), since the birthstones diamond texture looks cool. The display names for all of the items will say "White Diamond". (planned: recipe to make it into regular diamond)
* No shields & armor (planned as separate mod: birthstones_3d_armor)
* No arrows (planned as separate mod: birthstones_throwing)

### Future plans
* Look into changes in "birthstones fixed" at https://forum.minetest.net/viewtopic.php?f=9&t=11497&hilit=birthstones
* Look into overlap in stone list found in Glooptest
* Make compatible with glooptest
```lua
	local glooptest = minetest.get_modpath("glooptest")
	if glooptest then
		register_alias("birthstones:amethyst","glooptest:amethyst_gem")
		register_alias("birthstones:emerald","glooptest:emerald_gem")
		register_alias("birthstones:ruby","glooptest:ruby_gem")
		register_alias("birthstones:sapphire","glooptest:sapphire_gem")
		register_alias("birthstones:topaz","glooptest:topaz_gem")
		-- (and glooptest:*_block for all of those)
	else
		-- create those ores
		-- register those ore nodes
		-- register those block nodes
	end
	-- If neeeded, can also do things like drop = glooptest and "glooptest:topaz_gem" or "birthstones:topaz"
```


## Minerals of note not in birthstones (for reference only) with density values from website above:
MORE but with hardness values available from 18carat.co.uk link above:
* Name,Density,Moh,Brinell
* Apatite,3.16-3.23,5,137
* Calcite,2.69-2.71,3,53

### Developer Notes
xcf file has colors used for manual tinting

(If you rotate the gems, rotation must be applied, since absorption is manually done along object z axis--see "Blender gem tutorial" link below for why)
Do the following steps to re-render a block:
* Open the included Blend file in Blender and set the input nodes as follows (if there are two, set one as the input for absorption and turn that up--or experiment; ~ means wasn't plugged into any nodes):
(v1L you can also tweak whether fresnel, facing, or IsTransmissionRay is Factor for "Glow Mix" node (you can also flip the inputs)
(v2 you can also tweak whether Tangent, which Light Path output [and whether passes through Reduction node], or nothing [0.00] is used for Glare Mix's Factor; warped block shards can be fitted together then scaled by 1.01 on the x&z [s, shift z, 1.01])
Name,		GemColor,		IOR**,	Scatter,Gloss,	Clarity,Absorption,	AbsSat,	Glare Mix
Alexandrite,567274 to 63152c,1.75,	~,		~,		.95,		1,		1.0,	Gem:Tangent ; Block: Tangent*Reduction; Block east: 0.00
Amethyst,	ad87a6,			1.55,	.5,		0,		0,		1,			.5
Aquamarine,	8bdcdf,			,	,		,		,		,			
Diamond,	ced7da,			,	,		,		,		,			
Emerald,	02552a,			,	,		,		,		,			
Garnet,		78200c,			,	,		,		,		,			
Opal,		(texture),		,	,		,		,		,			
Peridot,	85b116,			,	,		,		,		,			
Ruby,		832935,			,	,		,		,		,			
Sapphire,	163f7d,			,	,		,		,		,			
Topaz, 		E5A55F,			1.62,	.5,		.5,		1.0, 	0.0,		0.0
Zircon,		255f75,			,	,		,		,		,			
Take note that this list is in alphabetical order (like birthstones-mod git 2012) for convenience, not in actual birthstone month order.
* Keep default resolution of 32x32 (must be full bleed then cropped to 16x16 manually to avoid edge issues with cycles)
* Render the following cameras (or experiment): North, East, Top
* In your favorite image editor, finish making them usable in-game:
	* Crop all textures to 16x16
	* Make the textures seemless such as by using these steps:
		* Copy the bottom row of pixels of top, then Paste onto top row of pixels of north
		* Rotate top to the right temporarilty (don't save top after this)
		* Copy the new bottom row of pixels of top, then Paste onto top row of pixels of east


### Special Thanks
Blender gem tutorial
https://www.youtube.com/watch?v=3EN6mAFDqaI
by Marijus Jacevičius


Complete IOR List
** http://forums.cgsociety.org/archive/index.php?t-513458.html


## Minetest 2017 API notes
(see http://wiki.minetest.net/Groups and https://github.com/minetest/minetest/blob/142e2d3b74ad886eed83b0fc9d6cfea100dae10a/doc/lua_api.txt#L736 )
### groupcaps (in tool_capabilities dict in register_tool 2nd param dict): a dictionary of groupcap dictionaries such as:
* choppy: chops wood
* snappy: leaves and other thin materials -- possible with sword, but wears sword out quickly
* fleshy: damage mobs/players
* crumbly: shovels etc
* cracky: picks etc
(and more unrelated to this mod)

### register_node:
http://dev.minetest.net/minetest.register_node
http://dev.minetest.net/Groups
* groups.cracky: like other dig types, the value is normally 1 to 3, and 1 requires the best pick to mine.
* groups.level: prevents being mined by lower level stuff