v/vlib/gg/text_rendering.v

194 lines
4.8 KiB
V

// Copyright (c) 2019-2020 Alexander Medvednikov. All rights reserved.
// Use of this source code is governed by an MIT license that can be found in the LICENSE file.
module gg
import sokol.sfons
import gx
import os
struct FT {
pub:
fons &C.FONScontext
font_normal int
font_bold int
font_mono int
font_italic int
scale f32 = 1.0
}
struct FTConfig {
font_path string
scale f32 = 1.0
font_size int
}
fn new_ft(c FTConfig) ?&FT{
if c.font_path == '' {
// Load default font
}
$if !android {
if c.font_path == '' || !os.exists(c.font_path) {
println('failed to load font "$c.font_path"')
return none
}
}
mut bytes := []byte{}
$if android {
bytes = os.read_apk_asset(c.font_path) or {
println('failed to load font "$c.font_path"')
return none
}
} $else {
bytes = os.read_bytes(c.font_path) or {
println('failed to load font "$c.font_path"')
return none
}
}
bold_path := 'SFNS-bold.ttf'// c.font_path.replace('.ttf', '-bold.ttf')
bytes_bold := os.read_bytes(bold_path) or {
println('failed to load font "$bold_path"')
bytes
}
mono_path := '/System/Library/Fonts/SFNSMono.ttf'// c.font_path.replace('.ttf', '-bold.ttf')
bytes_mono:= os.read_bytes(mono_path) or {
println('failed to load font "$mono_path"')
bytes
}
italic_path := '/System/Library/Fonts/SFNSItalic.ttf'
bytes_italic:= os.read_bytes(italic_path) or {
println('failed to load font "$italic_path"')
bytes
}
fons := sfons.create(512, 512, 1)
return &FT{
fons : fons
font_normal: C.fonsAddFontMem(fons, 'sans', bytes.data, bytes.len, false)
font_bold: C.fonsAddFontMem(fons, 'sans', bytes_bold.data, bytes_bold.len, false)
font_mono: C.fonsAddFontMem(fons, 'sans', bytes_mono.data, bytes_mono.len, false)
font_italic: C.fonsAddFontMem(fons, 'sans', bytes_italic.data, bytes_italic.len, false)
scale: c.scale
}
}
fn (ctx &Context) set_cfg(cfg gx.TextCfg) {
if !ctx.font_inited {
return
}
if cfg.bold {
ctx.ft.fons.set_font(ctx.ft.font_bold)
}
else if cfg.mono {
ctx.ft.fons.set_font(ctx.ft.font_mono)
}
else if cfg.italic {
ctx.ft.fons.set_font(ctx.ft.font_italic)
}
else {
ctx.ft.fons.set_font(ctx.ft.font_normal)
}
scale := if ctx.ft.scale == 0 { f32(1) } else { ctx.ft.scale }
size := if cfg.mono { cfg.size - 2 } else { cfg.size }
ctx.ft.fons.set_size(scale * f32(size))
C.fonsSetAlign(ctx.ft.fons, int(cfg.align) | int(cfg.vertical_align))
color := C.sfons_rgba(cfg.color.r, cfg.color.g, cfg.color.b, 255)
C.fonsSetColor(ctx.ft.fons, color)
ascender := f32(0.0)
descender := f32(0.0)
lh := f32(0.0)
ctx.ft.fons.vert_metrics(&ascender, &descender, &lh)
}
pub fn (ctx &Context) draw_text(x, y int, text_ string, cfg gx.TextCfg) {
if !ctx.font_inited {
eprintln('gg: draw_text(): font not initialized')
return
}
//text := text_.trim_space() // TODO remove/optimize
mut text := text_
if text.contains('\t') {
text = text.replace('\t', ' ')
}
ctx.set_cfg(cfg)
scale := if ctx.ft.scale == 0 { f32(1) } else { ctx.ft.scale }
C.fonsDrawText(ctx.ft.fons, x * scale, y * scale, text.str, 0) // TODO: check offsets/alignment
}
pub fn (ctx &Context) draw_text_def(x, y int, text string) {
ctx.draw_text(x, y, text, {})
}
/*
pub fn (mut gg FT) init_font() {
}
*/
pub fn (ft &FT) flush(){
sfons.flush(ft.fons)
}
pub fn (ctx &Context) text_width(s string) int {
// ctx.set_cfg(cfg) TODO
if !ctx.font_inited {
return 0
}
mut buf := [4]f32{}
C.fonsTextBounds(ctx.ft.fons, 0, 0, s.str, 0, buf)
if s.ends_with(' ') {
return int((buf[2] - buf[0]) / ctx.scale) + ctx.text_width('i') // TODO fix this in fontstash?
}
return int((buf[2] - buf[0]) / ctx.scale)
}
pub fn (ctx &Context) text_height(s string) int {
// ctx.set_cfg(cfg) TODO
if !ctx.font_inited {
return 0
}
mut buf := [4]f32{}
C.fonsTextBounds(ctx.ft.fons, 0, 0, s.str, 0, buf)
return int((buf[3] - buf[1]) / ctx.scale)
}
pub fn (ctx &Context) text_size(s string) (int, int) {
// ctx.set_cfg(cfg) TODO
if !ctx.font_inited {
return 0,0
}
mut buf := [4]f32{}
C.fonsTextBounds(ctx.ft.fons, 0, 0, s.str, 0, buf)
return int((buf[2] - buf[0]) / ctx.scale), int((buf[3] - buf[1]) / ctx.scale)
}
pub fn system_font_path() string {
env_font := os.getenv('VUI_FONT')
if env_font != '' && os.exists(env_font) {
return env_font
}
$if windows {
return 'C:\\Windows\\Fonts\\arial.ttf'
}
mut fonts := ['Ubuntu-R.ttf', 'Arial.ttf', 'LiberationSans-Regular.ttf', 'NotoSans-Regular.ttf',
'FreeSans.ttf', 'DejaVuSans.ttf']
$if macos {
return '/System/Library/Fonts/SFNS.ttf'
//fonts = ['SFNS.ttf', 'SFNSText.ttf']
}
s := os.exec('fc-list') or { panic('failed to fetch system fonts') }
system_fonts := s.output.split('\n')
for line in system_fonts {
for font in fonts {
if line.contains(font) && line.contains(':') {
res := line.all_before(':')
println('Using font $res')
return res
}
}
}
panic('failed to init the font')
}