More examples about Fonts

[zstyblik]

Hello,

I believe more examples about Fonts and Font configuration would be nice, although it's possible it's my fault.
I've tried to draw a string on GNU/Linux and kept failing. This is because of two things. I don't have a luxi font and FontFileName() makes platform/OS(?) specific assumptions about TTF font filenames. But looking at the filenames at my GNU/Linux in /usr/share/fonts/truetype/freefont, there is no predictable way to determine filenames. Therefore, it seems to me like specific FontFileName() might be needed ... a lot.

So, here is an example for my specific case:

package main

import (
    "image"

    "github.com/llgcode/draw2d"
    "github.com/llgcode/draw2d/draw2dimg"
)

func MyFontFileName(fontData draw2d.FontData) string {
    fontFileName := fontData.Name
    switch fontData.Family {
    case draw2d.FontFamilySans:
        fontFileName += "Sans"
    case draw2d.FontFamilySerif:
        fontFileName += ""
    case draw2d.FontFamilyMono:
        fontFileName += "Mono"
    }
    if fontData.Style&draw2d.FontStyleBold != 0 {
        fontFileName += "Bold"
    } else {
        fontFileName += ""
    }

    if fontData.Style&draw2d.FontStyleItalic != 0 {
        fontFileName += "Italic"
    }
    fontFileName += ".ttf"
    return fontFileName
}

func main() {
    // Initialize the graphic context on an RGBA image
    dest := image.NewRGBA(image.Rect(0, 0, 297, 210))
    gc := draw2dimg.NewGraphicContext(dest)
    // This is to get FreeMonoBold.ttf
    fontData := draw2d.FontData{
        Name:   "Free",
        Family: draw2d.FontFamilyMono,
        Style:  draw2d.FontStyleBold,
    }
    draw2d.SetFontFolder("/usr/share/fonts/truetype/freefont")
    draw2d.SetFontNamer(MyFontFileName)
    gc.SetFontData(fontData)

    gc.FillStringAt("Hello world", 10, 40)
    draw2dimg.SaveToPngFile("/dev/shm/hello.png", dest)
}

As I've said, it might be me I haven't figured it out immediately. But it might help to have it in examples or documentation.

Thanks.

[llgcode]

You're right it would be nice to have more doc on it this one seems to be a good one. We have already a PR on FontCache that can have impact on this #94