x.ttf: vfmt the examples in the README.md

pull/10559/head
Delyan Angelov 2021-06-24 11:13:57 +03:00
parent f18265e6a8
commit 96adfc9d5b
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1 changed files with 64 additions and 63 deletions

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@ -22,10 +22,10 @@ At this point the font "arial" is loaded and parsed and if it is a valid TTF fon
ready for the rendering.
We can get some quick info on the font as string using the `get_info_string` function:
```v ignore
```v oksyntax
println(ttf_font.get_info_string())
```
that give an outpul like this:
produces an output like this:
```
----- Font Info -----
font_family : Arial
@ -56,10 +56,11 @@ Let's start with a simple snippet of code:
```v oksyntax
import os
import x.ttf
[console]
fn main(){
fn main() {
mut ttf_font := ttf.TTF_File{}
ttf_font.buf = os.read_bytes("arial.ttf") or { panic(err) }
ttf_font.buf = os.read_bytes('arial.ttf') or { panic(err) }
ttf_font.init()
// print font info
println(ttf_font.get_info_string())
@ -75,20 +76,20 @@ import os
import x.ttf
[console]
fn main(){
fn main() {
mut ttf_font := ttf.TTF_File{}
ttf_font.buf = os.read_bytes("arial.ttf") or { panic(err) }
ttf_font.buf = os.read_bytes('arial.ttf') or { panic(err) }
ttf_font.init()
// print font info
println(ttf_font.get_info_string())
bmp_width := 200
bmp_width := 200
bmp_heigth := 64
bmp_layers := 4 // number of planes for an RGBA buffer
bmp_layers := 4 // number of planes for an RGBA buffer
// memory size of the buffer
bmp_size := bmp_width * bmp_heigth * bmp_layers
bmp_size := bmp_width * bmp_heigth * bmp_layers
font_size := 32 // font size in points
font_size := 32 // font size in points
device_dpi := 72 // default screen DPI
// Formula for scale calculation
// scaler := (font_size * device dpi) / (72dpi * em_unit)
@ -97,21 +98,21 @@ fn main(){
y_base := int((ttf_font.y_max - ttf_font.y_min) * scale)
// declare the bitmap struct
mut bmp:= ttf.BitMap{
tf : &ttf_font
buf : malloc(bmp_size)
buf_size : bmp_size
width : bmp_width
height : bmp_heigth
bp : bmp_layers
color : 0x000000_FF // RGBA black
scale : scale
mut bmp := ttf.BitMap{
tf: &ttf_font
buf: malloc(bmp_size)
buf_size: bmp_size
width: bmp_width
height: bmp_heigth
bp: bmp_layers
color: 0x000000_FF // RGBA black
scale: scale
}
bmp.init_filler()
bmp.clear()
bmp.set_pos(10,y_base)
bmp.draw_text("Test Text!")
bmp.save_as_ppm("test.ppm")
bmp.set_pos(10, y_base)
bmp.draw_text('Test Text!')
bmp.save_as_ppm('test.ppm')
}
```
This is the low level render that draw ther text on a bitmap and save the bitmap on a disk as
@ -126,7 +127,7 @@ You can specify the style for the text rendering in the `BitMap` struct::
enum Style {
outline
outline_aliased
filled // default syle
filled // default syle
raw
}
```
@ -139,20 +140,20 @@ import os
import x.ttf
[console]
fn main(){
fn main() {
mut ttf_font := ttf.TTF_File{}
ttf_font.buf = os.read_bytes("arial.ttf") or { panic(err) }
ttf_font.buf = os.read_bytes('arial.ttf') or { panic(err) }
ttf_font.init()
// print font info
println(ttf_font.get_info_string())
bmp_width := 200
bmp_width := 200
bmp_heigth := 200
bmp_layers := 4 // number of planes for an RGBA buffer
bmp_layers := 4 // number of planes for an RGBA buffer
// memory size of the buffer
bmp_size := bmp_width * bmp_heigth * bmp_layers
bmp_size := bmp_width * bmp_heigth * bmp_layers
font_size := 32 // font size in points
font_size := 32 // font size in points
device_dpi := 72 // default screen DPI
// Formula for scale calculation
// scaler := (font_size * device dpi) / (72dpi * em_unit)
@ -166,41 +167,42 @@ But Vwill prevail for sure, V is the way!!
òàèì@ò!£$%&
"
// declare the bitmap struct
mut bmp:= ttf.BitMap{
tf : &ttf_font
buf : malloc(bmp_size)
buf_size : bmp_size
width : bmp_width
height : bmp_heigth
bp : bmp_layers
color : 0x000000_FF // RGBA black
scale : scale
mut bmp := ttf.BitMap{
tf: &ttf_font
buf: malloc(bmp_size)
buf_size: bmp_size
width: bmp_width
height: bmp_heigth
bp: bmp_layers
color: 0x000000_FF // RGBA black
scale: scale
}
bmp.init_filler()
bmp.clear()
bmp.justify = true
bmp.align = .left
bmp.draw_text_block(text, {x: 0, y:0, w: bmp_width-20, h: bmp_heigth})
bmp.save_as_ppm("test.ppm")
bmp.align = .left
bmp.draw_text_block(text, x: 0, y: 0, w: bmp_width - 20, h: bmp_heigth)
bmp.save_as_ppm('test.ppm')
}
```
This is the low level render that draw text block on the bitmap.
A text block is defined from a `Text_block` struct:
```v
struct Text_block {
x int // x postion of the left high corner
y int // y postion of the left high corner
w int // width of the text block
h int // heigth of the text block
cut_lines bool = true // force to cut the line if the length is over the text block width
x int // x postion of the left high corner
y int // y postion of the left high corner
w int // width of the text block
h int // heigth of the text block
cut_lines bool = true // force to cut the line if the length is over the text block width
}
```
and use the following bitmap fields:
```v oksyntax
```v ignore
style Style = .filled // default syle
align Text_align = .left // default text align
justify bool // justify text flag, default deactivated
justify_fill_ratio f32 = 0.5 // justify fill ratio, if the ratio of the filled row is >= of this then justify the text
justify_fill_ratio f32 = 0.5 // justify fill ratio, if the ratio of the filled
// row is >= of this then justify the text
```
It is possible to modify these parameters to obtain the desired effect on the text rendering.
@ -216,7 +218,6 @@ import gg
import gx
import sokol.sapp
import sokol.sgl
import x.ttf
import os
@ -225,7 +226,7 @@ const (
win_height = 700
bg_color = gx.white
font_paths = [
"arial.ttf"
'arial.ttf',
]
)
@ -236,16 +237,16 @@ pub mut:
init_flag bool
frame_c int
tf []ttf.TTF_File
ttf_render []ttf.TTF_render_Sokol
tf []ttf.TTF_File
ttf_render []ttf.TTF_render_Sokol
}
fn my_init(mut app App_data) {
app.init_flag = true
}
fn draw_frame(mut app &App_data) {
cframe_txt := "Current Frame: $app.frame_c"
fn draw_frame(mut app App_data) {
cframe_txt := 'Current Frame: $app.frame_c'
app.gg.begin()
@ -258,7 +259,7 @@ fn draw_frame(mut app &App_data) {
// update the text
mut txt1 := &app.ttf_render[0]
txt1.destroy_texture()
txt1.create_text(cframe_txt ,43)
txt1.create_text(cframe_txt, 43)
txt1.create_texture()
txt1.draw_text_bmp(app.gg, 30, 60)
}
@ -267,12 +268,12 @@ fn draw_frame(mut app &App_data) {
}
[console]
fn main(){
fn main() {
mut app := &App_data{
gg: 0
}
app.gg = gg.new_context({
app.gg = gg.new_context(
width: win_width
height: win_height
create_window: true
@ -281,26 +282,26 @@ fn main(){
bg_color: bg_color
frame_fn: draw_frame
init_fn: my_init
})
)
// load TTF fonts
for font_path in font_paths {
mut tf := ttf.TTF_File{}
tf.buf = os.read_bytes(font_path) or { panic(err) }
println("TrueTypeFont file [$font_path] len: ${tf.buf.len}")
println('TrueTypeFont file [$font_path] len: $tf.buf.len')
tf.init()
println(tf.get_info_string())
app.tf << tf
}
// TTF render 0 Frame counter
app.ttf_render << &ttf.TTF_render_Sokol {
app.ttf_render << &ttf.TTF_render_Sokol{
bmp: &ttf.BitMap{
tf: &(app.tf[0])
buf: malloc(32000000)
buf: unsafe { malloc(32000000) }
buf_size: (32000000)
color : 0xFF0000FF
//style: .raw
color: 0xFF0000FF
// style: .raw
}
}