v/gg/gg.v

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// Copyright (c) 2019 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 stbi
import glm
import gl
#flag darwin -I/usr/local/Cellar/freetype/2.10.0/include/freetype2
#flag -lfreetype
#flag linux -I/usr/include/freetype2
#flag linux -I.
#include "ft2build.h"
#include FT_FREETYPE_H
#include "glad.h"
struct Vec2 {
x int
y int
}
import const (
GL_STATIC_DRAW
GL_FLOAT
GL_FALSE
GL_UNSIGNED_INT
GL_INT
)
const (
DEFAULT_FONT_SIZE = 12
)
pub fn vec2(x, y int) Vec2 {
res := Vec2 {
x: x,
y: y,
}
return res
}
struct Character {
texture_id u32
size Vec2
bearing Vec2
advance u32
}
pub fn init() {
println(gl.TEXT_VERT)
gl.init_glad()
}
struct Face {
cobj voidptr
kek int
}
struct Cfg {
width int
height int
use_ortho int
retina bool
font_size int
}
struct GG {
shader gl.Shader
// use_ortho bool
width int
height int
VAO u32
rect_vao u32
rect_vbo u32
line_vao u32
line_vbo u32
VBO u32
chars []gg.Character
utf_runes []string
utf_chars []gg.Character
text_ctx *GG
face Face
scale int // retina = 2 , normal = 1
}
// fn new_context(width, height int, use_ortho bool, font_size int) *GG {
pub fn new_context(cfg Cfg) *GG {
// println('new context orhto=$cfg.use_ortho')
// # glScissor(0,0,300,300);
shader := gl.new_shader('simple')
shader.use()
if cfg.use_ortho > 0 {
projection := glm.ortho(0, cfg.width, cfg.height, 0)
/*
// for debugging broken tetris in gg.o
# projection.data[0]=0.010000;
# projection.data[1]=0.000000;
# projection.data[2]=0.000000;
# projection.data[3]=0.000000;
# projection.data[4]=0.000000;
# projection.data[5]=-0.005000;
# projection.data[6]=0.000000;
# projection.data[7]=0.000000;
# projection.data[8]=0.000000;
# projection.data[9]=0.000000;
# projection.data[10]=1.000000;
# projection.data[11]=0.000000;
# projection.data[12]=-1.000000;
# projection.data[13]=1.000000;
# projection.data[14]=0.000000;
# projection.data[15]=1.000000;
*/
// projection_new := ortho(0, width, height, 0)
// println('\nORTHO OLD=')
# for (int i=0;i<16;i++) printf("%d=%f ",i, projection.data[i]);
// println('\n\n!ORTHO NEW=')
// # for (int i=0;i<16;i++) printf("%d=%f ",i, projection_new[i]);
// println('\n\n')
println('setting o')
shader.set_mat4('projection', projection)
}
else {
// TODO move to function (allow volt functions to return arrrays without allocations)
// i := glm.identity3()
shader.set_mat4('projection', glm.identity())
}
VAO := gl.gen_vertex_array()
println('new gg context VAO=$VAO')
VBO := gl.gen_buffer()
mut scale := 1
if cfg.retina {
scale = 2
}
mut ctx := &GG {
shader: shader,
width: cfg.width,
height: cfg.height,
VAO: VAO,
VBO: VBO,
// /line_vao: gl.gen_vertex_array()
// /line_vbo: gl.gen_buffer()
text_ctx: new_context_text(cfg, scale),
scale: scale
// use_ortho: use_ortho
}
// ctx.init_rect_vao()
return ctx
}
pub fn (ctx &GG) draw_triangle(x1, y1, x2, y2, x3, y3 f32, c gx.Color) {
// println('draw_triangle $x1,$y1 $x2,$y2 $x3,$y3')
ctx.shader.use()
ctx.shader.set_color('color', c)
vertices := [
x1, y1, 0,
x2, y2, 0,
x3, y3, 0,
] !
// bind the Vertex Array Object first, then bind and set vertex buffer(s),
// and then configure vertex attributes(s).
gl.bind_vao(ctx.VAO)
gl.set_vbo(ctx.VBO, vertices, GL_STATIC_DRAW)
gl.vertex_attrib_pointer(0, 3, GL_FLOAT, false, 3, 0)
gl.enable_vertex_attrib_array(0)
// gl.bind_buffer(GL_ARRAY_BUFFER, uint(0))
// You can unbind the VAO afterwards so other VAO calls won't accidentally modify this VAO,
// but this rarely happens. Modifying other
// VAOs requires a call to glBindVertexArray anyways so we generally don't unbind VAOs
// (nor VBOs) when it's not directly necessary.
// gl.bind_vertex_array(uint(0))
// gl.bind_vertex_array(ctx.VAO)
gl.draw_arrays(GL_TRIANGLES, 0, 3)
}
pub fn (ctx &GG) draw_triangle_tex(x1, y1, x2, y2, x3, y3 f32, c gx.Color) {
ctx.shader.use()
ctx.shader.set_color('color', c)
ctx.shader.set_int('has_texture', 1)
vertices := [
x1, y1, 0, 0, 0, 0, 1, 1,
x2, y2, 0, 0, 0, 0, 1, 0,
x3, y3, 0, 0, 0, 0, 0, 0,
] !
gl.bind_vao(ctx.VAO)
gl.set_vbo(ctx.VBO, vertices, GL_STATIC_DRAW)
// position attribute
gl.vertex_attrib_pointer(0, 3, GL_FLOAT, false, 3, 0)
gl.enable_vertex_attrib_array(0)
// color attribute
gl.vertex_attrib_pointer(1, 3, GL_FLOAT, false, 8, 3)
gl.enable_vertex_attrib_array(1)
// texture attribute
gl.vertex_attrib_pointer(2, 2, GL_FLOAT, false, 8, 6)
gl.enable_vertex_attrib_array(2)
// /
// gl.draw_arrays(GL_TRIANGLES, 0, 3)
gl.draw_elements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0)
}
pub fn (ctx &GG) draw_rect(x, y, w, h f32, c gx.Color) {
// println('gg.draw_rect($x,$y,$w,$h)')
// wrong order
// // ctx.draw_triangle(x, y, x + w, y, x + w, y + h, c)
// // ctx.draw_triangle(x, y, x, y + h, x + w, y + h, c)
// good order. counter clock wise
// ctx.draw_triangle(x, y, x, y + h, x + w, y + h, c)
// ctx.draw_triangle(x, y, x + w, y + h, x + w, y, c)
ctx.draw_rect2(x, y, w, h, c)
}
/*
fn (ctx mut GG) init_rect_vao() {
ctx.rect_vao = gl.gen_vertex_array()
ctx.rect_vbo = gl.gen_buffer()
vertices := [
x + w, y, 0,
x + w, y + h, 0,
x, y + h, 0,
x, y, 0,
] !
indices := [
0, 1, 3,// first triangle
1, 2, 3// second triangle
] !
gl.bind_vao(ctx.rect_vao)
gl.set_vbo(ctx.rect_vbo, vertices, GL_STATIC_DRAW)
ebo := gl.gen_buffer()
// ///////
gl.set_ebo(ebo, indices, GL_STATIC_DRAW)
}
*/
pub fn (ctx &GG) draw_rect2(x, y, w, h f32, c gx.Color) {
C.glDeleteBuffers(1, &ctx.VAO)
C.glDeleteBuffers(1, &ctx.VBO)
ctx.shader.use()
ctx.shader.set_color('color', c)
ctx.shader.set_int('has_texture', 0)
// 4--1
// 3--2
$if linux {
// y += h
}
vertices := [
x + w, y, 0,
x + w, y + h, 0,
x, y + h, 0,
x, y, 0,
] !
indices := [
0, 1, 3,// first triangle
1, 2, 3// second triangle
] !
gl.bind_vao(ctx.VAO)
gl.set_vbo(ctx.VBO, vertices, GL_STATIC_DRAW)
ebo := gl.gen_buffer()
// ///////
gl.set_ebo(ebo, indices, GL_STATIC_DRAW)// !!! LEAKS
// /////
gl.vertex_attrib_pointer(0, 3, GL_FLOAT, false, 3, 0)
gl.enable_vertex_attrib_array(0)
// gl.bind_vao(ctx.rect_vao)
gl.bind_vao(ctx.VAO)
gl.draw_elements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0)
C.glDeleteBuffers(1, &ebo)
}
// jfn ft_load_char(face FT_Face, code FT_ULong) Character {
// fn ft_load_char(_face voidptr, _code voidptr) Character {
fn ft_load_char(_face Face, code i64) Character {
// #FT_Face face = *(FT_Face*)(_face); FT_ULong code = *(FT_ULong*)(code);
# FT_Face face = *((FT_Face*)_face.cobj);
# if (FT_Load_Char(face, code, FT_LOAD_RENDER))
{
println('freetype: Failed to load Glyph')
exit(1)
}
// Generate texture
# GLuint texture;
# glGenTextures(1, &texture);
# glBindTexture(GL_TEXTURE_2D, texture);
# glTexImage2D(
# GL_TEXTURE_2D,
# 0,
# GL_RED,
# face->glyph->bitmap.width,
# face->glyph->bitmap.rows,
# 0,
# GL_RED,
# GL_UNSIGNED_BYTE,
# face->glyph->bitmap.buffer
# );
// Set texture options
# glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
# glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
# glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
# glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// Now store character for later use
ch := Character{}
# ch.texture_id=texture ;
# ch.size = gg__vec2(face->glyph->bitmap.width, face->glyph->bitmap.rows);
# ch.bearing = gg__vec2(face->glyph->bitmap_left, face->glyph->bitmap_top),
# ch.advance = face->glyph->advance.x;
return ch
}
pub fn new_context_text(cfg Cfg, scale int) *GG {
// Can only have text in ortho mode
if !cfg.use_ortho {
return &GG{text_ctx: 0}
}
mut width := cfg.width * scale
mut height := cfg.height * scale
font_size := cfg.font_size * scale
// exit('fs=$font_size')
// if false {
// retina
// width = width * 2// scale// 2
// height = height * 2// scale// 2
// font_size *= scale// 2
// }
/*
gl.viewport(0, 0, width, height)
*/
// gl.enable(GL_CULL_FACE) // TODO NEED CULL? MEANS SHIT IS BROKEN?
gl.enable(GL_BLEND)
// return &GG{}
# glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
shader := gl.new_shader('text')
shader.use()
projection := glm.ortho(0, width, 0, height)// 0 at BOT
// projection_new := ortho(0, width, 0, height)// 0 at BOT
// projection := gl.ortho(0, width,height,0) // 0 at TOP
shader.set_mat4('projection', projection)
// FREETYPE
# FT_Library ft;
// All functions return a value different than 0 whenever an error occurred
# if (FT_Init_FreeType(&ft))
println('ERROR::FREETYPE: Could not init FreeType Library')
// Load font as face
// face := FT_Face{}
mut font_path := 'RobotoMono-Regular.ttf'
if !os.file_exists(font_path) {
font_path = '/var/tmp/RobotoMono-Regular.ttf'
}
if !os.file_exists(font_path) {
println('failed to load RobotoMono-Regular.ttf')
exit(1)
}
# FT_Face face;
# if (FT_New_Face(ft, font_path.str, 0, &face))
// # if (FT_New_Face(ft, "/Library/Fonts/Courier New.ttf", 0, &face))
// # if (FT_New_Face(ft, "/System/Library/Fonts/Apple Color Emoji.ttc", 0, &face))
{
println('freetyp: Failed to load font')
exit(1)
}
// Set size to load glyphs as
# FT_Set_Pixel_Sizes(face, 0, font_size) ;
// Disable byte-alignment restriction
# glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
// Gen texture
// Load first 128 characters of ASCII set
mut chars := []gg.Character{}
f := Face {
cobj: 0
kek: 0
}
# f.cobj = &face;
// # for (GLubyte c = 0; c < 128; c++)
for c := 0; c < 128; c++ {
// ch := Character{}
// ch:=ft_load_char(face, c)
// # ch =gg__ft_load_char(&face, &c);
// ////////////////////////////////
mut ch := ft_load_char(f, i64(c))
// s := utf32_to_str(uint(0x043f))
// s := 'п'
// ch = ft_load_char(f, s.utf32_code())
// # ch = gg__ft_load_char(f, 0x043f); // RUS P
// # unsigned long c = FT_Get_Char_Index(face, 0x043f );
// # printf("!!!!!!!!! %lu\n", c);
// # c = FT_Get_Char_Index(face, 0xd0bf );
// # printf("!!!!!!!!! %lu\n", c);
// # ch = gg__ft_load_char(f, 0xd0bf) ; // UTF 8
chars << ch
}
ch := Character{}
// # ch = gg__ft_load_char(f, 0x0000043f);
// # ch = gg__ft_load_char(f, 128169);
// chars.push(ch)
// Configure VAO
VAO := gl.gen_vertex_array()
println('new gg text context VAO=$VAO')
VBO := gl.gen_buffer()
gl.bind_vao(VAO)
gl.bind_buffer(GL_ARRAY_BUFFER, VBO)
// # glBufferData(GL_ARRAY_BUFFER, sizeof(GLf32) * 6 * 4, NULL, GL_DYNAMIC_DRAW);
gl.enable_vertex_attrib_array(0)
gl.vertex_attrib_pointer(0, 4, GL_FLOAT, false, 4, 0)
// # glVertexAttribPointer(0, 4, GL_FLOAT,false, 4 * sizeof(GLf32), 0);
// gl.bind_buffer(GL_ARRAY_BUFFER, uint(0))
// # glBindVertexArray(0);
mut ctx := &GG {
shader: shader,
width: width,
height: height,
scale: scale
VAO: VAO,
VBO: VBO,
chars: chars,
face: f
text_ctx: 0
}
ctx.init_utf8_runes()
return ctx
}
// A dirty hack to implement rendering of cyrillic letters.
// All UTF-8 must be supported.
fn (ctx mut GG) init_utf8_runes() {
s := 'йцукенгшщзхъфывапролджэячсмитьбюЙЦУКЕНГШЩЗХЪФЫВАПРОЛДЖЭЯЧСМИТЬБЮ'
println(s)
us := s.ustring()
for i := 0; i < us.len; i++ {
_rune := us.at(i)
ch := ft_load_char(ctx.face, _rune.utf32_code())
// ctx.utf_rune_map.set(rune, ch)
ctx.utf_runes << _rune
ctx.utf_chars << ch
}
}
// fn (ctx &GG) render_text(text string, x, y, scale f32, color gx.Color) {
pub fn (ctx &GG) draw_text(_x, _y int, text string, cfg gx.TextCfg) {
// dont draw non ascii for now
/*
for i := 0; i < text.len; i++ {
c := text[i]
if int(c) > 128 {
// ctx.text_ctx._draw_text(_x, _y, '[NON ASCII]', cfg)
// return
}
}
*/
// # glScissor(0,0,300,300);
utext := text.ustring_tmp()
// utext := text.ustring()
ctx.text_ctx._draw_text(_x, _y, utext, cfg)
// utext.free()
// # glScissor(0,0,ctx->width*2,ctx->height*2);
// gl.disable(GL_SCISSOR_TEST)// TODO
// #free(text.str);
}
fn (ctx &GG) draw_text_fast(_x, _y int, text ustring, cfg gx.TextCfg) {
ctx.text_ctx._draw_text(_x, _y, text, cfg)
}
// TODO HACK with second text context
// fn (ctx &GG) _draw_text(_x, _y int, text string, cfg gx.TextCfg) {
fn (ctx &GG) _draw_text(_x, _y int, utext ustring, cfg gx.TextCfg) {
/*
if utext.s.contains('on_seg') {
println('\nat(0)')
println(utext.runes)
firstc := utext.at(0)
println('drawtext "$utext.s" len=$utext.s.len ulen=$utext.len x=$_x firstc=$firstc')
if firstc != ' ' {
exit(1)
}
}
*/
// println('scale=$ctx.scale size=$cfg.size')
if cfg.align == gx.ALIGN_RIGHT {
width := utext.len * 7
_x -= width + 10
}
x := f32(_x) * ctx.scale// f32(2)
// println('y=$_y height=$ctx.height')
// _y = _y * int(ctx.scale) //+ 26
_y = _y * int(ctx.scale) + ((cfg.size * ctx.scale) / 2) + 5 * ctx.scale
y := f32(ctx.height - _y)
color := cfg.color
// Activate corresponding render state
ctx.shader.use()
ctx.shader.set_color('textColor', color)
# glActiveTexture(GL_TEXTURE0);
gl.bind_vao(ctx.VAO)
// Iterate through all characters
// utext := text.ustring()
for i := 0; i < utext.len; i++ {
_rune := utext.at(i)
// println('$i => $_rune')
mut ch := Character{}
if _rune.len == 1 {
idx := _rune[0]
if idx < 0 || idx >= ctx.chars.len {
println('BADE RUNE $_rune')
continue
}
ch = ctx.chars[_rune[0]]
}
else if _rune.len > 1 {
// TODO O(1) use map
for j := 0; j < ctx.utf_runes.len; j++ {
rune_j := ctx.utf_runes[j]
// if string_eq(ctx.utf_runes[j], rune) {
if rune_j==_rune {
ch = ctx.utf_chars[j]
break
}
}
}
if ch.size.x == 0 {
// continue
}
// mut c := int(text[i])
// c = 128
// s := 'A'
// c := int(s[0])
// ch := ctx.chars[c]
xpos := x + f32(ch.bearing.x) * 1
ypos := y - f32(ch.size.y - ch.bearing.y) * 1
w := f32(ch.size.x) * 1
h := f32(ch.size.y) * 1
// Update VBO for each character
# GLfloat vertices[6][4] = {
# { xpos, ypos + h, 0.0, 0.0 },
# { xpos, ypos, 0.0, 1.0 },
# { xpos + w, ypos, 1.0, 1.0 },
# { xpos, ypos + h, 0.0, 0.0 },
# { xpos + w, ypos, 1.0, 1.0 },
# { xpos + w, ypos + h, 1.0, 0.0 }
# };
// t := glfw.get_time()
// Render glyph texture over quad
// t1 := glfw.get_time()
# glBindTexture(GL_TEXTURE_2D, ch.texture_id);
// Update content of VBO memory
gl.bind_buffer(GL_ARRAY_BUFFER, ctx.VBO)
// t2 := glfw.get_time()
// # glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(vertices), vertices); // Be sure to use glBufferSubData and not glBufferData
# glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_DYNAMIC_DRAW);
// t3 := glfw.get_time()
// gl.bind_buffer(GL_ARRAY_BUFFER, uint(0))
// t4 := glfw.get_time()
// Render quad
gl.draw_arrays(GL_TRIANGLES, 0, 6)
// t5 := glfw.get_time()
// # if (glfw__get_time() - t > 0.001)
// {
// # printf("do_text = %f '%s' \n", glfw__get_time() - t, text.str);
// # printf("t1=%f, t2=%f, t3=%f, t4=%f, t5=%f\n\n\n", t1-t, t2-t1, t3-t2, t4-t3, t5-t4);
// }
// Now advance cursors for next glyph (note that advance is number of 1/64 pixels)
// Bitshift by 6 to get value in pixels (2^6 = 64 (divide amount of 1/64th pixels by 64 to get amount of pixels))
# x += (ch.advance >> 6) * 1;
}
gl.bind_vao(u32(0))
# glBindTexture(GL_TEXTURE_2D, 0);
// runes.free()
// #free(runes.data);
}
fn (ctx &GG) draw_text_def(x, y int, text string) {
cfg := gx.TextCfg {
color: gx.Black,
size: DEFAULT_FONT_SIZE,
align: gx.ALIGN_LEFT,
}
ctx.draw_text(x, y, text, cfg)
}
fn update() {
// # ui__post_empty_event();
}
pub fn (c GG) circle(x, y, r int) {
}
fn (c GG) fill_color(color gx.Color) {
}
fn (c GG) fill() {
}
fn (c GG) move_to(x, y int) {
}
fn (c GG) line_to(x, y int) {
}
fn (c GG) stroke_width(size int) {
}
fn (c GG) stroke_color(color gx.Color) {
}
fn (c GG) stroke() {
}
fn (c GG) save() {
}
fn (c GG) restore() {
}
fn (c GG) intersect_scissor(x, y, w, h int) {
}
fn (c GG) translate(x, y int) {
}
fn (c GG) create_font(name, file string) int {
return 0
}
fn (c GG) text(x, y int, text string) {
}
fn (c GG) text_box(x, y, max int, text string) {
}
fn (c GG) font_face(f string) {
}
fn (c GG) font_size(size int) {
}
fn (c GG) text_align(a int) {
}
pub fn create_image(file string) u32 {
println('gg create image "$file"')
if file.contains('twitch') {
return u32(0)// TODO
}
if !os.file_exists(file) {
println('gg create image no such file "$file"')
return u32(0)
}
texture := gl.gen_texture()
img := stbi.load(file)
gl.bind_2d_texture(texture)
img.tex_image_2d()
gl.generate_mipmap(GL_TEXTURE_2D)
img.free()
// println('gg end')
return texture
}
pub fn (ctx &GG) draw_line_c(x, y, x2, y2 int, color gx.Color) {
C.glDeleteBuffers(1, &ctx.VAO)
C.glDeleteBuffers(1, &ctx.VBO)
ctx.shader.use()
ctx.shader.set_color('color', color)
vertices := [f32(x), f32(y), f32(x2), f32(y2)] !
gl.bind_vao(ctx.VAO)
gl.set_vbo(ctx.VBO, vertices, GL_STATIC_DRAW)
gl.vertex_attrib_pointer(0, 2, GL_FLOAT, false, 2, 0)
gl.enable_vertex_attrib_array(0)
gl.bind_vao(ctx.VAO)
gl.draw_arrays(GL_LINES, 0, 2)
}
pub fn (c &GG) draw_line(x, y, x2, y2 int) {
c.draw_line_c(x, y, x2, y2, gx.Gray)
}
pub fn (c &GG) draw_vertical(x, y, height int) {
c.draw_line(x, y, x, y + height)
}
// fn (ctx &GG) draw_image(x, y, w, h f32, img stbi.Image) {
pub fn (ctx &GG) draw_image(x, y, w, h f32, tex_id u32) {
// println('DRAW IMAGE $x $y $w $h $tex_id')
ctx.shader.use()
// ctx.shader.set_color('color', c)
ctx.shader.set_int('has_texture', 1)
// 4--1
// | |
// 3--2
vertices := [
x + w, y, 0, 1, 0, 0, 1, 1,
x + w, y + h, 0, 0, 1, 0, 1, 0,
x, y + h, 0, 0, 0, 1, 0, 0,
x, y, 0, 1, 1, 0, 0, 1,
] !
indices := [
0, 1, 3,// first triangle
1, 2, 3// second triangle
] !
// VAO := gl.gen_vertex_array()
// VBO := gl.gen_buffer()
gl.bind_vao(ctx.VAO)
gl.set_vbo(ctx.VBO, vertices, GL_STATIC_DRAW)
ebo := gl.gen_buffer()
gl.set_ebo(ebo, indices, GL_STATIC_DRAW)
gl.vertex_attrib_pointer(0, 3, GL_FLOAT, false, 8, 0)
gl.enable_vertex_attrib_array(0)
gl.vertex_attrib_pointer(1, 3, GL_FLOAT, false, 8, 3)
gl.enable_vertex_attrib_array(1)
gl.vertex_attrib_pointer(2, 2, GL_FLOAT, false, 8, 6)
gl.enable_vertex_attrib_array(2)
gl.bind_2d_texture(u32(tex_id))
gl.bind_vao(ctx.VAO)
gl.draw_elements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0)
}
pub fn (c &GG) draw_empty_rect(x, y, w, h int, color gx.Color) {
c.draw_line_c(x, y, x + w, y, color)
c.draw_line_c(x, y, x, y + h, color)
c.draw_line_c(x, y + h, x + w, y + h, color)
c.draw_line_c(x + w, y, x + w, y + h, color)
}