v/examples/ttf_font/example_ttf.v

import gg
import gx
import sokol.sapp
import sokol.sgl

import x.ttf
import os
//import math

const (
	win_width  = 600
	win_height = 700
	bg_color   = gx.white
	font_paths = [
		"Imprima-Regular.ttf"
		"Graduate-Regular.ttf"
	]
)

/******************************************************************************
*
* UI 
*
*****************************************************************************/
struct App_data {
pub mut:
	gg        &gg.Context
	sg_img    C.sg_image
	init_flag bool
	frame_c   int
	
	tf              []ttf.TTF_File
	ttf_render      []ttf.TTF_render_Sokol
	text_ready_flag bool
	
	mouse_x   int = -1
	mouse_y   int = -1
}

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"
	
	app.gg.begin()

	sgl.defaults()
	sgl.matrix_mode_projection()
	sgl.ortho(0.0, f32(sapp.width()), f32(sapp.height()), 0.0, -1.0, 1.0)
	sgl.c4b(0, 0, 0, 255) // black

	// draw a line as background
	sgl.begin_line_strip()
	sgl.v2f(10, 10)
	sgl.v2f(100, 100)
	sgl.end()

	// draw text only if the app is already initialized
	if app.init_flag == true {
		sgl.begin_line_strip()
		sgl.v2f(410, 400)
		sgl.v2f(510, 400)
		sgl.end()
		
		// update the text
		mut txt1 := &app.ttf_render[0]
		if app.frame_c % 2 == 0 {
			txt1.destroy_texture()
			txt1.create_text(cframe_txt ,43)
			txt1.create_texture()
		}
 
		// ----- decomment if you want text rotation ----		
		//txt1.bmp.angle = 3.141592 / 180 * f32(app.frame_c % 360)
		//txt1.draw_text_bmp(app.gg, 300, 350)
		//txt1.bmp.angle =  0
		
		txt1.draw_text_bmp(app.gg, 30, 60)

		// block test
		block_txt := "Today it is a good day!
Tommorow I'm not so sure :(
Frame: $app.frame_c
But Vwill prevail for sure, V is the way!!
òàèì@ò!£$%&
"
		txt1 = &app.ttf_render[1]
		if app.frame_c % 2 == 0 {
			
			txt1.bmp.justify = false
			if (app.frame_c>>6) % 2 == 0 {
				//txt1.align = .left
				txt1.bmp.justify = true
			}
			
			txt1.bmp.align = .left
			if (app.frame_c>>6) % 3 == 0 {
				txt1.bmp.align = .right
			}
			txt1.destroy_texture()
			txt1.create_text_block(block_txt, 500, 500, 32)
			txt1.create_texture()
		}
		
		// decomment if want block color change
		//txt1.bmp.color = ttf.color_multiply(0xFF00FFFF, f32(app.frame_c % 255)/255.0)
		
		// decomment if want block rotation wanted
		//txt1.bmp.angle = 3.141592/180 * f32(app.frame_c % 45)
		
		txt1.draw_text_bmp(app.gg, 30 + (app.frame_c>>1) & 0xFF , 200)
		
		// draw mouse position
		if app.mouse_x >= 0 {
			txt1 = &app.ttf_render[2]
			txt1.destroy_texture()
			txt1.create_text("$app.mouse_x,$app.mouse_y",25)
			txt1.create_texture()
			r := app.mouse_x % 255
			g := app.mouse_y % 255
			color := u32(r << 24) | u32(g << 16) | 0xFF
			txt1.bmp.color = color
			txt1.draw_text_bmp(app.gg, app.mouse_x , app.mouse_y)
		}
		
		app.frame_c ++
	}
	
	app.gg.end()
}

fn my_event_manager(mut ev sapp.Event, mut app &App_data) {
	if ev.typ == .mouse_move {
		app.mouse_x = int(ev.mouse_x)
		app.mouse_y = int(ev.mouse_y)
	}
}

[console]
fn main(){
    
	mut app := &App_data{
		gg: 0
	}

	app.gg = gg.new_context({
		width: win_width
		height: win_height
		use_ortho: true // This is needed for 2D drawing
		create_window: true
		window_title: 'Test TTF module'
		user_data: app
		bg_color: bg_color
		frame_fn: draw_frame
		event_fn: my_event_manager
		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}")
		tf.init()
		println("Unit per EM: $tf.units_per_em")
		app.tf << tf
	}
	
	// TTF render 0 Frame counter
	app.ttf_render << &ttf.TTF_render_Sokol {
		bmp: &ttf.BitMap{
			tf: &(app.tf[0])
			buf: malloc(32000000)
			buf_size: (32000000)
			color : 0xFF0000FF
			//style: .raw
			//use_font_metrics: true
		}
	}
	
	// TTF render 1 Text Block
	app.ttf_render << &ttf.TTF_render_Sokol {
		bmp: &ttf.BitMap{
			tf: &(app.tf[1])
			//color : 0xFF0000_10
			//style: .raw
			//use_font_metrics: true
		}
	}
	
	// TTF mouse position render
	app.ttf_render << &ttf.TTF_render_Sokol {
		bmp: &ttf.BitMap{
			tf: &(app.tf[0])
		}
	}
	
	/* setup sokol_gfx */
	app.gg.run()
}