v/vlib/gg/text_rendering.v

371 lines
9.3 KiB
V

// Copyright (c) 2019-2021 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 sokol.sgl
import gx
import os
enum FontVariant {
normal = 0
bold
mono
italic
}
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
custom_bold_font_path string
scale f32 = 1.0
font_size int
bytes_normal []byte
bytes_bold []byte
bytes_mono []byte
bytes_italic []byte
}
struct StringToRender {
x int
y int
text string
cfg gx.TextCfg
}
fn new_ft(c FTConfig) ?&FT {
if c.font_path == '' {
if c.bytes_normal.len > 0 {
fons := sfons.create(512, 512, 1)
bytes_normal := c.bytes_normal
bytes_bold := if c.bytes_bold.len > 0 {
c.bytes_bold
} else {
debug_font_println('setting bold variant to normal')
bytes_normal
}
bytes_mono := if c.bytes_mono.len > 0 {
c.bytes_mono
} else {
debug_font_println('setting mono variant to normal')
bytes_normal
}
bytes_italic := if c.bytes_italic.len > 0 {
c.bytes_italic
} else {
debug_font_println('setting italic variant to normal')
bytes_normal
}
return &FT{
fons: fons
font_normal: C.fonsAddFontMem(fons, c'sans', bytes_normal.data, bytes_normal.len,
false)
font_bold: C.fonsAddFontMem(fons, c'sans', bytes_bold.data, bytes_bold.len,
false)
font_mono: C.fonsAddFontMem(fons, c'sans', bytes_mono.data, bytes_mono.len,
false)
font_italic: C.fonsAddFontMem(fons, c'sans', bytes_italic.data, bytes_italic.len,
false)
scale: c.scale
}
} else {
// Load default font
}
}
if c.font_path == '' || !os.exists(c.font_path) {
$if !android {
println('failed to load font "$c.font_path"')
return none
}
}
mut bytes := []byte{}
$if android {
// First try any filesystem paths
bytes = os.read_bytes(c.font_path) or { []byte{} }
if bytes.len == 0 {
// ... then try the APK asset path
bytes = os.read_apk_asset(c.font_path) or {
println('failed to load font "$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 := if c.custom_bold_font_path != '' {
c.custom_bold_font_path
} else {
get_font_path_variant(c.font_path, .bold)
}
bytes_bold := os.read_bytes(bold_path) or {
debug_font_println('failed to load font "$bold_path"')
bytes
}
mono_path := get_font_path_variant(c.font_path, .mono)
bytes_mono := os.read_bytes(mono_path) or {
debug_font_println('failed to load font "$mono_path"')
bytes
}
italic_path := get_font_path_variant(c.font_path, .italic)
bytes_italic := os.read_bytes(italic_path) or {
debug_font_println('failed to load font "$italic_path"')
bytes
}
fons := sfons.create(512, 512, 1)
return &FT{
fons: fons
font_normal: C.fonsAddFontMem(fons, c'sans', bytes.data, bytes.len, false)
font_bold: C.fonsAddFontMem(fons, c'sans', bytes_bold.data, bytes_bold.len, false)
font_mono: C.fonsAddFontMem(fons, c'sans', bytes_mono.data, bytes_mono.len, false)
font_italic: C.fonsAddFontMem(fons, c'sans', bytes_italic.data, bytes_italic.len,
false)
scale: c.scale
}
}
pub 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, cfg.color.a)
if cfg.color.a != 255 {
sgl.load_pipeline(ctx.timage_pip)
}
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 int, y int, text_ string, cfg gx.TextCfg) {
$if macos {
if ctx.native_rendering {
if cfg.align == gx.align_right {
width := ctx.text_width(text_)
C.darwin_draw_string(x - width, ctx.height - y, text_, cfg)
} else {
C.darwin_draw_string(x, ctx.height - y, text_, cfg)
}
return
}
}
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, &char(text_.str), 0) // TODO: check offsets/alignment
}
pub fn (ctx &Context) draw_text_def(x int, 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 {
$if macos {
if ctx.native_rendering {
return C.darwin_text_width(s)
}
}
// ctx.set_cfg(cfg) TODO
if !ctx.font_inited {
return 0
}
mut buf := [4]f32{}
C.fonsTextBounds(ctx.ft.fons, 0, 0, &char(s.str), 0, &buf[0])
if s.ends_with(' ') {
return int((buf[2] - buf[0]) / ctx.scale) +
ctx.text_width('i') // TODO fix this in fontstash?
}
res := int((buf[2] - buf[0]) / ctx.scale)
// println('TW "$s" = $res')
$if macos {
if ctx.native_rendering {
return res * 2
}
}
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, &char(s.str), 0, &buf[0])
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, &char(s.str), 0, &buf[0])
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 {
fonts = ['/System/Library/Fonts/SFNS.ttf', '/System/Library/Fonts/SFNSText.ttf',
'/Library/Fonts/Arial.ttf',
]
for font in fonts {
if os.is_file(font) {
return font
}
}
}
$if android {
xml_files := ['/system/etc/system_fonts.xml', '/system/etc/fonts.xml',
'/etc/system_fonts.xml', '/etc/fonts.xml', '/data/fonts/fonts.xml',
'/etc/fallback_fonts.xml',
]
font_locations := ['/system/fonts', '/data/fonts']
for xml_file in xml_files {
if os.is_file(xml_file) && os.is_readable(xml_file) {
xml := os.read_file(xml_file) or { continue }
lines := xml.split('\n')
mut candidate_font := ''
for line in lines {
if line.contains('<font') {
candidate_font = line.all_after('>').all_before('<').trim(' \n\t\r')
if candidate_font.contains('.ttf') {
for location in font_locations {
candidate_path := os.join_path(location, candidate_font)
if os.is_file(candidate_path) && os.is_readable(candidate_path) {
return candidate_path
}
}
}
}
}
}
}
}
s := os.execute('fc-list')
if s.exit_code != 0 {
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')
}
fn get_font_path_variant(font_path string, variant FontVariant) string {
// TODO: find some way to make this shorter and more eye-pleasant
// NotoSans, LiberationSans, DejaVuSans, Arial and SFNS should work
mut file := os.file_name(font_path)
mut fpath := font_path.replace(file, '')
file = file.replace('.ttf', '')
match variant {
.normal {}
.bold {
if fpath.ends_with('-Regular') {
file = file.replace('-Regular', '-Bold')
} else if file.starts_with('DejaVuSans') {
file += '-Bold'
} else if file.to_lower().starts_with('arial') {
file += 'bd'
} else {
file += '-bold'
}
$if macos {
if os.exists('SFNS-bold') {
file = 'SFNS-bold'
}
}
}
.italic {
if file.ends_with('-Regular') {
file = file.replace('-Regular', '-Italic')
} else if file.starts_with('DejaVuSans') {
file += '-Oblique'
} else if file.to_lower().starts_with('arial') {
file += 'i'
} else {
file += 'Italic'
}
}
.mono {
if !file.ends_with('Mono-Regular') && file.ends_with('-Regular') {
file = file.replace('-Regular', 'Mono-Regular')
} else if file.to_lower().starts_with('arial') {
// Arial has no mono variant
} else {
file += 'Mono'
}
}
}
return fpath + file + '.ttf'
}
fn debug_font_println(s string) {
$if debug_font ? {
println(s)
}
}