support vector of colors

Author: t-bltg

src/rendering.jl

@@ -37,14 +37,14 @@ Render `str` into `img` using the font `face` of size `pixelsize` at coordinates
 
 # Arguments
 * `y0,x0`: origin is in upper left with positive `y` going down
-* `fcolor`: foreground color; typemax(T) for T<:Integer, otherwise one(T)
+* `fcolor`: foreground color; AbstractVector{T}, typemax(T) for T<:Integer, otherwise one(T)
 * `bcolor`: background color; set to `nothing` for transparent
 * `halign`: :hleft, :hcenter, or :hright
 * `valign`: :vtop, :vcenter, :vbaseline, or :vbottom
 """
 function renderstring!(
         img::AbstractMatrix{T}, str::String, face::FTFont, pixelsize::Union{Int, Tuple{Int, Int}}, y0, x0;
-        fcolor::T = one_or_typemax(T), bcolor::Union{T,Nothing} = zero(T),
+        fcolor::Union{AbstractVector{T},T} = one_or_typemax(T), bcolor::Union{T,Nothing} = zero(T),
         halign::Symbol = :hleft, valign::Symbol = :vbaseline
     ) where T<:Union{Real,Colorant}
 
@@ -103,21 +103,27 @@ function renderstring!(
             px += kx
         end
 
+        fcol = if fcolor isa AbstractVector
+            fcolor[istr]
+        else
+            fcolor
+        end
+
         # trim parts of glyph images that are outside the destination
         cliprowlo, cliprowhi = max(0, -(py-by)), max(0, py - by + h - imgh)
         clipcollo, clipcolhi = max(0, -bx-px),   max(0, px + bx + w - imgw)
 
         if bcolor === nothing
             for row = 1+cliprowlo : h-cliprowhi, col = 1+clipcollo : w-clipcolhi
                 bitmaps[istr][col,row]==0 && continue
-                c1 = bitmaps[istr][col,row] / bitmapmax * fcolor
+                c1 = bitmaps[istr][col,row] / bitmapmax * fcol
                 img[row+py-by, col+px+bx] = T <: Integer ? round(T, c1) : T(c1)
             end
         else
             for row = 1+cliprowlo : h-cliprowhi, col = 1+clipcollo : w-clipcolhi
                 bitmaps[istr][col, row] == 0 && continue
                 w1 = bitmaps[istr][col, row] / bitmapmax
-                c1 = w1 * fcolor
+                c1 = w1 * fcol
                 c0 = (1.0 - w1) * bcolor
                 img[row + py - by, col + px + bx] = T <: Integer ? round(T, c1 + c0) : T(c1 + c0)
             end