Use mmapping to avoid unicode issues on windows (#94)

* load fonts from mmapped files to avoid unicode issues in freetype on windows

* add a test

---------

Co-authored-by: Simon <[email protected]>

Author: jkrumbiegel

Project.toml

@@ -8,13 +8,15 @@ ColorVectorSpace = "c3611d14-8923-5661-9e6a-0046d554d3a4"
 Colors = "5ae59095-9a9b-59fe-a467-6f913c188581"
 FreeType = "b38be410-82b0-50bf-ab77-7b57e271db43"
 GeometryBasics = "5c1252a2-5f33-56bf-86c9-59e7332b4326"
+Mmap = "a63ad114-7e13-5084-954f-fe012c677804"
 
 [compat]
 BaseDirs = "1"
 ColorVectorSpace = "0.8, 0.9, 0.10, 0.11"
 Colors = "0.11, 0.12, 0.13"
 FreeType = "4"
 GeometryBasics = "0.4.1, 0.5"
+Mmap = "1"
 julia = "1.6"
 
 [extras]

src/FreeTypeAbstraction.jl

@@ -6,6 +6,7 @@ import Base: /, *, ==, @lock
 import Base.Broadcast: BroadcastStyle, Style, broadcasted
 using GeometryBasics: StaticVector
 using BaseDirs
+import Mmap
 
 include("types.jl")
 include("findfonts.jl")

src/types.jl

@@ -30,6 +30,16 @@ function newface(facename, faceindex::Real=0, ftlib=FREE_FONT_LIBRARY)
     return face[]
 end
 
+function newface_mmapped(filepath, faceindex::Real=0, ftlib=FREE_FONT_LIBRARY)
+    mmapped = open(filepath, "r") do io
+        Mmap.mmap(io)
+    end
+    face = Ref{FT_Face}()
+    err = @lock LIBRARY_LOCK FT_New_Memory_Face(ftlib[1], mmapped, length(mmapped), Int32(faceindex), face)
+    check_error(err, "Couldn't load font \"$filepath\"")
+    return face[], mmapped
+end
+
 
 struct FontExtent{T}
     vertical_bearing::Vec{2, T}
@@ -135,9 +145,10 @@ mutable struct FTFont
     use_cache::Bool
     extent_cache::Dict{UInt64, FontExtent{Float32}}
     lock::ReentrantLock # lock this for the duration of any FT operation on ft_ptr
-    function FTFont(ft_ptr::FreeType.FT_Face, use_cache::Bool=true)
+    mmapped::Union{Nothing,Vector{UInt8}}
+    function FTFont(ft_ptr::FreeType.FT_Face, use_cache::Bool=true, mmapped = nothing)
         extent_cache = Dict{UInt64, FontExtent{Float32}}()
-        face = new(ft_ptr, use_cache, extent_cache, ReentrantLock())
+        face = new(ft_ptr, use_cache, extent_cache, ReentrantLock(), mmapped)
         finalizer(safe_free, face)
         return face
     end
@@ -146,7 +157,10 @@ end
 use_cache(face::FTFont) = getfield(face, :use_cache)
 get_cache(face::FTFont) = getfield(face, :extent_cache)
 
-FTFont(path::String) = FTFont(newface(path))
+function FTFont(path::String, use_cache::Bool=true)
+    face, mmapped = newface_mmapped(path)
+    FTFont(face, use_cache, mmapped)
+end
 
 # C interop
 Base.cconvert(::Type{FreeType.FT_Face}, font::FTFont) = font

test/runtests.jl

@@ -296,6 +296,15 @@ end
     end
 end
 
+@testset "Unicode in path" begin
+    mktempdir() do dir
+        path = joinpath(dir, "𝓜𝔂 𝔽𝕒𝕟𝕔𝕪 𝐅𝐨𝐧𝐭 🅵🅸🅻🅴.ttf")
+        cp(joinpath(@__DIR__, "hack_regular.ttf"), path)
+        f = FreeTypeAbstraction.FTFont(path)
+        @test repr(f) == "FTFont (family = Hack, style = Regular)"
+    end
+end
+
 @testset "Thread safety" begin
     mktempdir() do dir
         n = 100