summaryrefslogtreecommitdiff
path: root/Master/texmf-dist/tex/generic/pgfplots/lua/pgfplots/streamer.lua
blob: ab5b605d6d1527125cc9a49fb65821cbc21c5aae (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
-- Contains coordinate streamers, i.e. classes which generate coordinates and stream them to some output stream

local math=math
local pgfplotsmath = pgfplots.pgfplotsmath
local type=type
local tostring=tostring
local error=error
local table=table

do
-- all globals will be read from/defined in pgfplots:
local _ENV = pgfplots
-----------------------------------

CoordOutputStream = newClass()

function CoordOutputStream:constructor()
end

-- @param pt an instance of Coord
function CoordOutputStream:coord(pt)
end

-----------------------------------

SurveyCoordOutputStream = newClassExtends(CoordOutputStream)

function SurveyCoordOutputStream:constructor(targetPlothandler)
	if not targetPlothandler then error("arguments must not be nil") end
	self.plothandler=  targetPlothandler
end

function SurveyCoordOutputStream:coord(pt)
	self.plothandler:surveypoint(pt)
end

-------------
-- This is a partial reimplementation of \addplot expression: it samples points -- but entirely in LUA. Only the results are serialized back to TeX.

AddplotExpressionCoordinateGenerator = newClass()

function AddplotExpressionCoordinateGenerator:constructor(coordoutputstream, expressionsByDimension, domainMin, domainMax, samples, variableNames)
	if not coordoutputstream or not expressionsByDimension or not domainMin or not domainMax or not samples or not variableNames then error("arguments must not be nil") end
	if #variableNames ~= 2 then error("Expected 2 variableNames") end
	self.coordoutputstream = coordoutputstream
	self.is3d = #expressionsByDimension == 3
	self.expressions = expressionsByDimension
	self.domainMin = domainMin
	self.domainMax = domainMax
	self.samples = samples
	self.variableNames = variableNames
	
	-- log("initialized " .. tostring(self) .. "\n")
end

-- @return true on success or false if the operation cannot be carried out.
-- this method is a replicate of \pgfplots@addplotimpl@expression@@
function AddplotExpressionCoordinateGenerator:generateCoords()
	local stringToFunctionMap = pgfluamathfunctions.stringToFunctionMap
	-- create a backup of the 'x' and 'y' math expressions which 
	-- have been defined in \pgfplots@coord@stream@start:
	local old_global_function_x = stringToFunctionMap["x"]
	local old_global_function_y = stringToFunctionMap["y"]

	local coordoutputstream = self.coordoutputstream
	local is3d = self.is3d
	local expressions = self.expressions
	local xExpr = expressions[1]
	local yExpr = expressions[2]
	local zExpr = expressions[3]

	local domainMin = self.domainMin
	local domainMax = self.domainMax
	local samples = self.samples
	local h = {}
	for i = 1,#domainMin do
		h[i] = (domainMax[i] - domainMin[i]) / (samples[i]-1)
	end

	local variableNames = self.variableNames
	
	local x,y
	local sampleLine = #samples==1
	
	local function pseudoconstantx() return x end
	local pseudoconstanty
	if sampleLine then
		if yExpr ~= variableNames[2] then
			-- suppress the warning - we want to allow (x,y,x^2) in this case.
			pseudoconstanty = function() return 0 end
		else
			local didWarn = false
			pseudoconstanty = function()
				if not didWarn then
					log("Sorry, you can't use 'y' in this context. PGFPlots expected to sample a line, not a mesh. Please use the [mesh] option combined with [samples y>0] and [domain y!=0:0] to indicate a twodimensional input domain\n")
					didWarn = true
				end
				return 0
			end
		end
	else
		pseudoconstanty = function() return y end
	end

	local pgfmathparse = pgfluamathparser.pgfmathparse
	local prepareX
	if xExpr == variableNames[1] then
		prepareX = function() return x end
	else
		prepareX = function() return pgfmathparse(xExpr) end
	end

	local prepareY
	if yExpr == variableNames[2] then
		prepareY = function() return y end
	else
		prepareY = function() return pgfmathparse(yExpr) end
	end

	local function computeXYZ()
		stringToFunctionMap[variableNames[1]] = pseudoconstantx
		stringToFunctionMap[variableNames[2]] = pseudoconstanty
		local X = prepareX()
		local Y = prepareY()
		local Z = nil
		if is3d then
			Z = pgfmathparse(zExpr)
		end
		
		local pt = Coord.new()
		pt.x = { X, Y, Z}

		-- restore 'x' and 'y'
		-- FIXME : defining the resulting x/y coordinates as 'x' and 'y' constants was a really really bad idea in the first place :-(
		stringToFunctionMap["x"] = old_global_function_x
		stringToFunctionMap["y"] = old_global_function_y

		coordoutputstream:coord(pt)
	end
	
	if not sampleLine then
		local xmin = domainMin[1]
		local ymin = domainMin[2]
		local hx = h[1]
		local hy = h[2]
		local max_i = samples[1]-1
		local max_j = samples[2]-1
		-- samples twodimensionally (a lattice):
		for j = 0,max_j do
			-- FIXME : pgfplots@plot@data@notify@next@y
			y = ymin + j*hy
			-- log("" .. j .. "\n")
			for i = 0,max_i do
				-- FIXME : pgfplots@plot@data@notify@next@x
				x = xmin + i*hx
				computeXYZ()
			end
			-- FIXME : \pgfplotsplothandlernotifyscanlinecomplete
		end
	else
		local xmin = domainMin[1]
		local hx = h[1]
		local max_i = samples[1]-1
		for i = 0,max_i do
			-- FIXME : pgfplots@plot@data@notify@next@x
			x = xmin + i*hx
			computeXYZ()
		end
	end
	
	stringToFunctionMap[variableNames[1]] = nil
	stringToFunctionMap[variableNames[2]] = nil
	return true
end

function AddplotExpressionCoordinateGenerator:__tostring()
	local result = "AddplotExpressionCoordinateGenerator[\n"
	result = result .. "\n  variable(s)=" .. self.variableNames[1] .. " " .. self.variableNames[2]
	result = result .. "\n  expressions="
	for i = 1,#self.expressions do
		result = result .. self.expressions[i] ..", "
	end
	result = result .. "\n  domain=" .. self.domainMin[1] .. ":" .. self.domainMax[1]
	result = result .. "\n  samples=" .. self.samples[1] 
	if #self.domainMin == 2 then
		result = result .. "\n  domain y=" .. self.domainMin[2] .. ":" .. self.domainMax[2]
		result = result .. "\n  samples y=" .. self.samples[2] 
	end
	result = result .. "]"
	return result
end

end