Merge pull request #67 from Kolaru/full_unicode_font

Good support for NewComputerModern font

Author: Kolaru

.github/workflows/ci.yml

@@ -15,8 +15,8 @@ jobs:
       fail-fast: false
       matrix:
         version:
+          - '1.7'
           - '1.6'
-          - '1.3'
         os:
           - ubuntu-latest
         arch:

Project.toml

@@ -1,7 +1,7 @@
 name = "MathTeXEngine"
 uuid = "0a4f8689-d25c-4efe-a92b-7142dfc1aa53"
 authors = ["Benoît Richard <kolaru@hotmail.com>"]
-version = "0.4.3"
+version = "0.5.0"
 
 [deps]
 AbstractTrees = "1520ce14-60c1-5f80-bbc7-55ef81b5835c"
@@ -18,8 +18,8 @@ Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 AbstractTrees = "0.3, 0.4"
 Automa = "0.8"
 DataStructures = "0.18"
-FreeTypeAbstraction = "0.9"
+FreeTypeAbstraction = "0.10"
 GeometryBasics = "0.4.1, 0.4.2"
 LaTeXStrings = "1.2"
 RelocatableFolders = "0.1, 0.2, 0.3"
-julia = "1.3"
+julia = "1.6"

prototype/Project.toml

@@ -1,6 +1,9 @@
 [deps]
+Cairo = "159f3aea-2a34-519c-b102-8c37f9878175"
 CairoMakie = "13f3f980-e62b-5c42-98c6-ff1f3baf88f0"
 Colors = "5ae59095-9a9b-59fe-a467-6f913c188581"
+FreeType = "b38be410-82b0-50bf-ab77-7b57e271db43"
+FreeTypeAbstraction = "663a7486-cb36-511b-a19d-713bb74d65c9"
 GeometryBasics = "5c1252a2-5f33-56bf-86c9-59e7332b4326"
 LaTeXStrings = "b964fa9f-0449-5b57-a5c2-d3ea65f4040f"
 Makie = "ee78f7c6-11fb-53f2-987a-cfe4a2b5a57a"

prototype/glyphtest.jl

@@ -0,0 +1,12 @@
+using Pkg
+
+Pkg.activate("prototype")
+
+using MathTeXEngine
+using CairoMakie
+
+tex = L"\int dx \theta 2 x"
+text(0, 0 ; text = tex, textsize=20)
+
+
+elems = generate_tex_elements(tex)

prototype/prototype.jl

@@ -17,7 +17,8 @@ draw_texelement!(args... ; size=64) = nothing
 function draw_texelement!(ax, texchar::TeXChar, position, scale ; size=64)
     x = position[1] * size
     y = position[2] * size
-    text!(ax, string(texchar.char), font=texchar.font,
+    # TODO This doesn't make sense anymore
+    text!(ax, string(Char(texchar.represented_char)), font=texchar.font,
         position=Point2f(x, y),
         textsize=size*scale,
         space=:data,
@@ -151,9 +152,14 @@ begin  # Quick test
     ax = Axis(fig[2, 1])
     hidedecorations!(ax)
     ax.aspect = DataAspect()
-    tex = L"3\degree \partial \sum \lim_{L →\infty} \gamma A^\sqrt{A + j + 2 + 3 + 2 + L} z^2 = \sum_{k = 1}^N \vec{v}_{(a + \bar{a})_k} + \sqrt{j} x! \quad \mathrm{when} \quad \sqrt{\frac{\Omega-2}{4+a+x}} < \int_{0}^{2π} |\sin(\mu x)| dx"
+    tex = L"\nabla 3\degree \partial L^3 \sum \lim_{L →\infty}
+            \varphi \phi \varpi \pi \varepsilon \epsilon
+            ℝ^\sqrt{A + j + 2 + 3} |x^2|^3 = \sum_{k = 1}^N
+            \vec{v}_{(a' + \bar{a})_k} + \sqrt{T} x! \quad \mathrm{when} \quad
+            \left[ \sqrt{\frac{\Omega-2}{a \langle c^\dagger \rangle b}} \right]^3_3 
+            < \int_{0}^{2π} |\sin(\mu x)| dx"
 
     makie_tex!(ax, tex, debug=true, size=64)
     fig[3, 1] = Label(fig, tex, tellwidth=false, tellheight=false, textsize=40)
     fig
-end
+end

src/MathTeXEngine.jl

@@ -14,7 +14,8 @@ using REPL.REPLCompletions: latex_symbols
 using RelocatableFolders
 
 import FreeTypeAbstraction:
-    ascender, boundingbox, descender, get_extent, hadvance, inkheight, inkwidth,
+    ascender, boundingbox, descender, get_extent, glyph_index,
+    hadvance, inkheight, inkwidth,
     height_insensitive_boundingbox, leftinkbound, rightinkbound,
     topinkbound, bottominkbound
 
@@ -23,6 +24,7 @@ const re = Automa.RegExp
 export TeXExpr, texparse
 export TeXElement, TeXChar, VLine, HLine, generate_tex_elements
 export get_font, get_fontpath
+export glyph_index
 
 # Reexport from LaTeXStrings
 export @L_str
@@ -33,6 +35,7 @@ include("parser/commands_registration.jl")
 include("parser/parser.jl")
 
 include("engine/computer_modern_data.jl")
+include("engine/new_computer_modern_data.jl")
 include("engine/fonts.jl")
 include("engine/layout_context.jl")
 include("engine/texelements.jl")

src/engine/computer_modern_data.jl

@@ -228,15 +228,15 @@ _latex_to_computer_modern = Dict(
 )
 
 
-_symbol_to_computer_modern = Dict{Char, Tuple{String, Char}}()
+_symbol_to_computer_modern = Dict{Char, Tuple{String, Int}}()
 
-for (symbol, (fontname, id)) in _latex_to_computer_modern
+for (symbol, (fontname, glyph_id)) in _latex_to_computer_modern
     if haskey(latex_symbols, symbol)
         symbol = latex_symbols[symbol][1]
     else
         symbol = symbol[1]
     end
 
     fontpath = joinpath("ComputerModern", "$fontname.ttf")
-    _symbol_to_computer_modern[symbol] = (fontpath, Char(id))
+    _symbol_to_computer_modern[symbol] = (fontpath, glyph_id)
 end

src/engine/fonts.jl

@@ -25,7 +25,15 @@ end
 # Loading the font directly here lead to FreeTypeAbstraction to fail with error
 # code 35, because handles to fonts are C pointer that cannot be fully
 # serialized at compile time
-const _default_fonts = Dict(
+const _new_computer_modern_fonts = Dict(
+    :regular => joinpath("NewComputerModern", "NewCMMath-Regular.otf"),
+    :italic => joinpath("NewComputerModern", "NewCM10-Italic.otf"),
+    :bold => joinpath("NewComputerModern", "NewCM10-Bold.otf"),
+    :bolditalic => joinpath("NewComputerModern", "NewCM10-BoldItalic.otf"),
+    :math => joinpath("NewComputerModern", "NewCMMath-Regular.otf")
+)
+
+const _computer_modern_fonts = Dict(
     :regular => joinpath("ComputerModern", "cmr10.ttf"),
     :italic => joinpath("ComputerModern", "cmmi10.ttf"),
     :bold => joinpath("ComputerModern", "cmb10.ttf"),
@@ -69,19 +77,33 @@ struct FontFamily
     fonts::Dict{Symbol, String}
     font_mapping::Dict{Symbol, Symbol}
     font_modifiers::Dict{Symbol, Dict{Symbol, Symbol}}
-    special_chars::Dict{Char, Tuple{String, Char}}
+    special_chars::Dict{Char, Tuple{String, Int}}
     slant_angle::Float64
     thickness::Float64
 end
 
-FontFamily(fonts) = FontFamily(
-    fonts,
-    _default_font_mapping,
-    _default_font_modifiers,
-    _symbol_to_computer_modern,
-    15,
-    0.0375)
-FontFamily() = FontFamily(_default_fonts)
+FontFamily() = FontFamily("NewComputerModern")
+FontFamily(fontname) = default_font_families[fontname]
+
+# These two fonts internals are very different, despite their similar names
+# We only try to fully support NewComputerModern, the other is here as it may
+# sometime provide quickfix solution to bug
+const default_font_families = Dict(
+    "NewComputerModern" => FontFamily(
+        _new_computer_modern_fonts,
+        _default_font_mapping,
+        _default_font_modifiers,
+        _symbol_to_new_computer_modern,
+        13,
+        0.0375),
+    "ComputerModern" => FontFamily(
+        _computer_modern_fonts,
+        _default_font_mapping,
+        _default_font_modifiers,
+        _symbol_to_computer_modern,
+        15,
+        0.0375)
+)
 
 """
     get_font([font_family=FontFamily()], fontstyle)
@@ -118,19 +140,10 @@ The thickness of the underline for the given font set.
 """
 thickness(font_family::FontFamily) = font_family.thickness
 
-"""
-    xheight(font::FTFont)
-
-The height of the letter x in the given font, i.e. the height of the letters
-without neither ascender nor descender.
-"""
-xheight(font::FTFont) = inkheight(TeXChar('x', font))
-
-
 """
     xheight(font::FontFamily)
 
 The height of the letter x in the given font family, i.e. the height of the letters
 without neither ascender nor descender.
 """
-xheight(font_family) = xheight(get_font(font_family, :regular))
+xheight(font_family) = inkheight(TeXChar('x', LayoutState(font_family), :text))

src/engine/layout.jl

@@ -27,14 +27,6 @@ function tex_layout(expr, state)
         if head in [:char, :delimiter, :digit, :punctuation, :symbol]
             char = args[1]
             texchar = TeXChar(char, state, head)
-
-            if char == '°'
-                return Group(
-                    [texchar],
-                    [Point2f(-0.2, 0)],
-                    [1]
-                )
-            end
             return texchar
         elseif head == :combining_accent
             accent, core = tex_layout.(args, state)
@@ -52,21 +44,20 @@ function tex_layout(expr, state)
                 [core, accent],
                 Point2f[
                     (0, 0),
-                    (x + hmid(core) - hmid(accent), y)
+                    (x + hmid(core) - hmid(accent), 0)
                 ],
                 [1, 1]
             )
         elseif head == :decorated
             core, sub, super = tex_layout.(args, state)
-            
-            core_width = hadvance(core)
 
+            # Should be a bit smarter for slanted font
             return Group(
                 [core, sub, super],
                 Point2f[
                     (0, 0),
-                    (core_width, -0.2),
-                    (core_width, 0.8 * xheight(core))],
+                    (rightinkbound(core) + 0.1, -0.2),
+                    (rightinkbound(core) + 0.1, 0.9 * xheight(core))],
                 [1, shrink, shrink]
             )
         elseif head == :delimited
@@ -129,26 +120,19 @@ function tex_layout(expr, state)
             return horizontal_layout(elements)
         elseif head == :integral
             pad = 0.1
-            sub, super = tex_layout.(args[2:3], state)
-
-            # Always use ComputerModern fallback for the integral sign
-            # as the Unicode LaTeX approach requires to use glyph variant
-            # which is unlikely to be supported by backends
-            intfont = load_font(joinpath("ComputerModern", "cmex10.ttf"))
-            int = TeXChar(Char(0x5a), intfont)
-            h = inkheight(int)
+            int, sub, super = tex_layout.(args, state)
 
             return Group(
                 [int, sub, super],
                 Point2f[
-                    (0, y_for_centered(font_family, int)),
+                    (0, 0),
                     (
                         0.15 - inkwidth(sub)*shrink/2,
-                        -h/2 + xheight(font_family)/2 - topinkbound(sub)*shrink - pad
+                        bottominkbound(int) - topinkbound(sub)*shrink - pad
                     ),
                     (
                         0.85 - inkwidth(super)*shrink/2,
-                        h/2 + xheight(font_family)/2 + pad
+                        topinkbound(int) + pad
                     )
                 ],
                 [1, shrink, shrink]
@@ -160,27 +144,24 @@ function tex_layout(expr, state)
             return horizontal_layout([Space(0.2), sym, Space(0.2)])
         elseif head == :sqrt
             content = tex_layout(args[1], state)
-            sqrt = TeXChar('√', state, :symbol)
-
-            relpad = 0.15
-
             h = inkheight(content)
-            ypad = relpad * h
-            h += 2ypad
-
-            if h > inkheight(sqrt)
-                sqrt = TeXChar('⎷', state, :symbol)
-                h = inkheight(sqrt)
-                y0 = (topinkbound(sqrt) - bottominkbound(sqrt))/2 + xheight(font_family)/2
-            else
-                y0 = bottominkbound(content) - bottominkbound(sqrt) - 0.1
+            sqrt = nothing
+
+            for name in ["radical.v1", "radical.v2", "radical.v3", "radical.v4"]
+                sqrt = TeXChar(name, state, :symbol ; represented = '√')
+                if inkheight(sqrt) >= 1.05h
+                    pad = (inkheight(sqrt) - 1.05h) / 2
+                    break
+                end
             end
 
-            lw = thickness(font_family)
+            h = inkheight(sqrt)
 
+            lw = thickness(font_family)
+            y0 = bottominkbound(content) - bottominkbound(sqrt) - pad
             y = y0 + topinkbound(sqrt) - lw
 
-            hline = HLine(inkwidth(content) + 0.1, lw)
+            hline = HLine(inkwidth(content) + pad, lw)
 
             return Group(
                 [sqrt, hline, content, Space(1.2)],
@@ -204,14 +185,7 @@ function tex_layout(expr, state)
 
             # The leftmost element must have x = 0
             x0 = -min(0, dxsub, dxsuper)
-
-            # Special case to deal with sum symbols and the like that do not
-            # have their baseline properly set in the font
-            if core isa TeXChar
-                y0 = y_for_centered(font_family, core)
-            else
-                y0 = 0.0
-            end
+            y0 = 0.0
 
             return Group(
                 [core, sub, super],

src/engine/new_computer_modern_data.jl

@@ -0,0 +1,46 @@
+_latex_to_new_computer_modern = Dict(
+    raw"\int" => 5930,
+    raw"\sum" => 5941,
+
+    raw"\partial" => 3377,
+    raw"\varepsilon" => 3378,
+    raw"\vartheta" => 3379,
+    raw"\varkappa" => 3380,
+    raw"\varphi" => 3381,
+    raw"\varrho" => 3382,
+    raw"\varpi" => 3383,
+
+    raw"\epsilon" => 3356,
+    raw"\theta" => 3359,
+    raw"\kappa" => 3361,
+    raw"\phi" => 3373,
+    raw"\rho" => 3368,
+    raw"\pi" => 3367
+)
+
+
+_symbol_to_new_computer_modern = Dict{Char, Tuple{String, Int}}()
+cmmath_fontpath = joinpath("NewComputerModern", "NewCMMath-Regular.otf")
+
+for (symbol,  glyph_id) in _latex_to_new_computer_modern
+    if haskey(latex_symbols, symbol)
+        symbol = latex_symbols[symbol][1]
+    else
+        symbol = symbol[1]
+    end
+    
+    _symbol_to_new_computer_modern[symbol] = (cmmath_fontpath, glyph_id)
+end
+
+# Standard hreek symbols : thin and italic
+for i in 0:24
+    capital = 'Α' + i
+    small = 'α' + i
+
+    if !haskey(_symbol_to_new_computer_modern, capital)
+        _symbol_to_new_computer_modern[capital] = (cmmath_fontpath, 3326 + i)
+    end
+    if !haskey(_symbol_to_new_computer_modern, small)
+        _symbol_to_new_computer_modern[small] = (cmmath_fontpath, 3352 + i)
+    end
+end