Module:Infobox dim - Revision history

Hike395: update latitude where zoom is correct to be closer to NA and Europe articles

2025-04-23T14:54:16Z

update latitude where zoom is correct to be closer to NA and Europe articles

← Previous revision		Revision as of 14:54, 23 April 2025
Line 9:		Line 9:
	-- On the equator, it's 305.748 meters/pixel according to https://wiki.openstreetmap.org/wiki/Zoom_levels		-- On the equator, it's 305.748 meters/pixel according to https://wiki.openstreetmap.org/wiki/Zoom_levels
	-- This quantity depends on the latitude (which we don't have easy access to)		-- This quantity depends on the latitude (which we don't have easy access to)
	-- Instead, we'll be correct at ~~30N~~, ~~cos(30~~ ~~degrees)~~ = ~~sqrt(3)/2~~		-- Instead, we'll be correct at 38 degrees N, given en-WP bias towards NA and Europe
			-- 38N was chosen because:
⚫	local metersPerPixelLevel9 = 305.748*math.~~sqrt~~(3)/2
			-- * It's the furthest north where scale=100000 maps to zoom=12
			-- * One hemisphere (20000km) maps to zoom=1
		⚫	local metersPerPixelLevel9 = 305.748*math.cos(math.rad(38))

	-- Convert from Geohack's scale to OSM style zoom levels as used by <maplink>		-- Convert from Geohack's scale to OSM style zoom levels as used by <maplink>
Line 107:		Line 110:
	scale = math.floor(scale+0.5)		scale = math.floor(scale+0.5)
	-- keep scale within sane bounds (OSM zoom levels 1-17)		-- keep scale within sane bounds (OSM zoom levels 1-17)
	if scale < ~~1800~~ then		if scale < 1600 then
	scale = ~~1800~~		scale = 1600
	end		end
	if scale > ~~225e6~~ then		if scale > 200e6 then
	scale = ~~225e6~~		scale = 200e6
	end		end
	return scale		return scale

Hike395: adjust scale safety levels to match integer OSM zoom levels

2025-04-22T10:54:25Z

adjust scale safety levels to match integer OSM zoom levels

← Previous revision		Revision as of 10:54, 22 April 2025
Line 106:		Line 106:
	if not scale then return end		if not scale then return end
	scale = math.floor(scale+0.5)		scale = math.floor(scale+0.5)
	-- keep scale within sane bounds		-- keep scale within sane bounds (OSM zoom levels 1-17)
	if scale < ~~2000~~ then		if scale < 1800 then
	scale = ~~2000~~		scale = 1800
	end		end
	if scale > ~~250e6~~ then		if scale > 225e6 then
	scale = ~~250e6~~		scale = 225e6
	end		end
	return scale		return scale

Hike395: bail early from geohackTypeToDim

2025-01-07T06:07:16Z

bail early from geohackTypeToDim

← Previous revision		Revision as of 06:07, 7 January 2025
Line 51:		Line 51:
	-- Convert from Geohack's types to Geohack dim		-- Convert from Geohack's types to Geohack dim
	local function geohackTypeToDim(args)		local function geohackTypeToDim(args)
	local ~~type~~ = args.type		local t = args.type
			if not t then return end
	local typeDim = mw.loadData('Module:Infobox_dim/data')		local typeDim = mw.loadData('Module:Infobox_dim/data')
	local dim = typeDim[~~type~~]		local dim = typeDim[t]
	local population = tonumber(args.population)		local population = tonumber(args.population)
	if ~~type~~ == 'city' and population and population > 0 then		if t == 'city' and population and population > 0 then
	-- assume city is a circle with density of 1000/square kilometer		-- assume city is a circle with density of 1000/square kilometer
	-- compute diameter, in meters. Then multiply by ~~1.954~~ to account for weird shapes		-- compute diameter, in meters. Then multiply by oddShape to account for weird shapes
	dim = 35.68e-3math.sqrt(population)oddShape		dim = 35.68e-3math.sqrt(population)oddShape
	-- don't zoom in too far		-- don't zoom in too far

Hike395: move code

2025-01-06T15:13:30Z

move code

@@ Line 17: / Line 17: @@
 	if not scale or scale <= 0 then return end
 	return math.log(metersPerPixelLevel9*ppm/scale)/log2 + 9
 end
@@ Line 134: / Line 113: @@
 	end
 	return scale
 end

Hike395: load main data, not sandbox

2025-01-06T15:02:33Z

load main data, not sandbox

← Previous revision		Revision as of 15:02, 6 January 2025
Line 73:		Line 73:
	local function geohackTypeToDim(args)		local function geohackTypeToDim(args)
	local type = args.type		local type = args.type
	local typeDim = mw.loadData('Module:Infobox_dim~~/sandbox~~/data')		local typeDim = mw.loadData('Module:Infobox_dim/data')
	local dim = typeDim[type]		local dim = typeDim[type]
	local population = tonumber(args.population)		local population = tonumber(args.population)

Hike395: check arguments more thoroughly

2024-11-04T14:01:26Z

check arguments more thoroughly

@@ Line 17: / Line 17: @@
 	if not scale or scale <= 0 then return end
 	return math.log(metersPerPixelLevel9*ppm/scale)/log2 + 9
 end
@@ Line 51: / Line 72: @@
 -- Convert from Geohack's types to Geohack dim
 local function geohackTypeToDim(args)
 	local type = args.type
-	local typeDim = mw.loadData('Module:Infobox_dim/data')
+	local typeDim = mw.loadData('Module:Infobox_dim/sandbox/data')
 	local dim = typeDim[type]
 	local population = tonumber(args.population)
@@ Line 80: / Line 100: @@
 -- compute geohack dim from unit arguments (e.g., length_mi)
 local function convertDim(args)
 	local length = args.length_mi and 1.60934*args.length_mi or args.length_km
 	local width = args.width_mi and 1.60934*args.width_mi or args.width_km
@@ Line 95: / Line 109: @@
 end
 	if args.scale then return args.scale end
 	local dim, units, scale
@@ Line 138: / Line 134: @@
 	end
 	return scale
 end
 function p._zoom(args)
 	args.viewport_px = args.viewport_px or 200 --- viewport for Kartographer is 200px high
-	local scale = p._scale(args)
+	local scale = computeScale(args)
 	if scale then
 		local zoom = geohackScaleToMapZoom(scale)

Hike395: add more comments

2024-10-23T15:16:48Z

add more comments

← Previous revision		Revision as of 15:16, 23 October 2024
Line 12:		Line 12:
	local metersPerPixelLevel9 = 305.748*math.sqrt(3)/2		local metersPerPixelLevel9 = 305.748*math.sqrt(3)/2

	-- Convert from Geohack's scale ~~and dim levels~~ to OSM style zoom levels as used by <maplink>		-- Convert from Geohack's scale to OSM style zoom levels as used by <maplink>
	local function geohackScaleToMapZoom(scale)		local function geohackScaleToMapZoom(scale)
	scale = tonumber(scale)		scale = tonumber(scale)
Line 19:		Line 19:
	end		end

			-- compute the viewport size (on screen) in meters, assuming ppm pixels per meter on screen
	local function computeViewport(args)		local function computeViewport(args)
	local viewport_cm = tonumber(args.viewport_cm)		local viewport_cm = tonumber(args.viewport_cm)
Line 24:		Line 25:
	return viewport_cm and viewport_cm / 100 or viewport_px and viewport_px / ppm		return viewport_cm and viewport_cm / 100 or viewport_px and viewport_px / ppm
	or tonumber(args.default_viewport) or 0.1		or tonumber(args.default_viewport) or 0.1
	end		end

			-- convert from geohack dim (knowing the viewpoint size on screen) to geohack scale
	local function geohackDimToScale(dim, args)		local function geohackDimToScale(dim, args)
	dim = tonumber(dim)		dim = tonumber(dim)
Line 47:		Line 49:
	local oddShape = 2.09 --- length/sqrt(area) of Boston (to choose an example)		local oddShape = 2.09 --- length/sqrt(area) of Boston (to choose an example)

	-- Convert from Geohack's types to Geohack's ~~scale levels~~		-- Convert from Geohack's types to Geohack dim
	local function geohackTypeToDim(args)		local function geohackTypeToDim(args)
	args = args or {}		args = args or {}
Line 66:		Line 68:
	end		end

	-- Convert from dimension of object to Geohack dim ~~level~~		-- Convert from dimension of object to Geohack dim
	local function computeDim(length,width,area)		local function computeDim(length,width,area)
	if length and width then		if length and width then
Line 76:		Line 78:
	end		end

			-- compute geohack dim from unit arguments (e.g., length_mi)
	local function convertDim(args)		local function convertDim(args)
	for _, arg in pairs({'length_mi','length_km','width_mi','width_km',		for _, arg in pairs({'length_mi','length_km','width_mi','width_km',

Hike395: correct handle viewport strings

2024-10-08T00:52:12Z

correct handle viewport strings

← Previous revision		Revision as of 00:52, 8 October 2024
Line 18:		Line 18:
	return math.log(metersPerPixelLevel9*ppm/scale)/log2 + 9		return math.log(metersPerPixelLevel9*ppm/scale)/log2 + 9
	end		end

			local function computeViewport(args)
			local viewport_cm = tonumber(args.viewport_cm)
			local viewport_px = tonumber(args.viewport_px)
		⚫	return viewport_cm and viewport_cm / 100 or viewport_px and viewport_px / ppm
			or tonumber(args.default_viewport) or 0.1
			end

	local function geohackDimToScale(dim, args)		local function geohackDimToScale(dim, args)
Line 27:		Line 34:
	dim = dim*1000		dim = dim*1000
	end		end
			return dim / computeViewport(args)
	local viewport = args.viewport_cm and args.viewport_cm / 100
	or args.viewport_px and args.viewport_px / ppm
	or args.default_viewport
	return dim / viewport
	end		end

Line 38:		Line 42:
	args = args or {}		args = args or {}
	if not scale or scale <= 0 then return end		if not scale or scale <= 0 then return end
		⚫	return scale * computeViewport(args) * 1e-3
	local viewport = args.viewport_cm and args.viewport_cm / 100
⚫	or ~~args.~~viewport_px and ~~args.~~viewport_px / ppm
	or args.default_viewport
⚫	return scale * ~~viewport~~ * 1e-3
	end		end

Hike395: make zoom correct at 30N rather than on equator

2024-10-07T16:09:20Z

make zoom correct at 30N rather than on equator

← Previous revision		Revision as of 16:09, 7 October 2024
Line 4:		Line 4:

	local log2 = 0.693147181		local log2 = 0.693147181
	local ppm = 1000/0.3 -- pixels per meter, from 0.3 mm / pixel		local ppm = 1000/0.3 -- pixels per meter, from 0.3 mm / pixel from https://wiki.openstreetmap.org/wiki/Zoom_levels

			-- To convert to OSM zoom level, we need to know meters per pixel at zoom level 9
		⚫	-- On the equator, it's 305.748 meters/pixel according to https://wiki.openstreetmap.org/wiki/Zoom_levels
			-- This quantity depends on the latitude (which we don't have easy access to)
			-- Instead, we'll be correct at 30N, cos(30 degrees) = sqrt(3)/2
			local metersPerPixelLevel9 = 305.748*math.sqrt(3)/2

	-- Convert from Geohack's scale and dim levels to OSM style zoom levels as used by <maplink>		-- Convert from Geohack's scale and dim levels to OSM style zoom levels as used by <maplink>
Line 10:		Line 16:
	scale = tonumber(scale)		scale = tonumber(scale)
	if not scale or scale <= 0 then return end		if not scale or scale <= 0 then return end
		⚫	return math.log(metersPerPixelLevel9*ppm/scale)/log2 + 9
⚫	-- ~~Approximation~~ of https://wiki.openstreetmap.org/wiki/Zoom_levels
	-- pixel/m from OSM is exact, so use zoom level 9 and 0.3 mm/pixel
⚫	return math.log(~~305.748~~*ppm/scale)/log2 + 9
	end		end

Hike395: choose an example (Boston) to set oddShape tweak factor

2024-10-07T03:40:33Z

choose an example (Boston) to set oddShape tweak factor

← Previous revision		Revision as of 03:40, 7 October 2024
Line 40:		Line 40:
	end		end

	local oddShape = 2.0		local oddShape = 2.09 --- length/sqrt(area) of Boston (to choose an example)

	-- Convert from Geohack's types to Geohack's scale levels		-- Convert from Geohack's types to Geohack's scale levels