vg_imgui.h

   1 /* Copyright (C) 2021-2024 Harry Godden (hgn) - All Rights Reserved */
   2
   3 /*
   4  *  Principles:
   5  *
   6  *    1. layout is defined by subdividing
   7  *    2. a parent node should never be resized by the content after creation
   8  *    3. when the ui is in an interactive state, no controls should ever move
   9  *    4. controls directly reference a memory location and use that as their
  10  *       unique id
  11  *    5. a maximum of ONE control per memory location can be drawn at any given
  12  *       point.
  13  */
  14
  15 #pragma once
  16
  17 #include "vg_engine.h"
  18 #include "vg_tex.h"
  19 #include "vg_shader.h"
  20 #include "vg_font.h"
  21
  22 extern vg_font_sheet vg_default_font_sheet;
  23 extern vg_font_face vgf_default_small, vgf_default_large, vgf_default_title;
  24
  25 typedef i16                             ui_px;
  26 typedef ui_px                           ui_rect[4];
  27 typedef ui_px           ui_point[2];
  28 typedef struct ui_vert  ui_vert;
  29
  30 enum ui_axis {
  31    k_ui_axis_h = 0x0u,
  32    k_ui_axis_v = 0x1u,
  33 };
  34
  35 /* Relative to cursor p0 */
  36 enum ui_align
  37 {  /*                         DC      BA */
  38    k_ui_align_lwr           =         0xff,
  39    k_ui_align_left          = 0x0000| 0x00,
  40    k_ui_align_right         = 0x0000| 0x01,
  41    k_ui_align_center        = 0x0000| 0x02,
  42
  43    k_ui_align_middle        = 0x0100,
  44    k_ui_align_middle_left   = 0x0100| 0x00,
  45    k_ui_align_middle_right  = 0x0100| 0x01,
  46    k_ui_align_middle_center = 0x0100| 0x02,
  47
  48    k_ui_align_bottom        = 0x0200,
  49    k_ui_align_bottom_left   = 0x0200| 0x00,
  50    k_ui_align_bottom_right  = 0x0200| 0x01,
  51    k_ui_align_bottom_center = 0x0200| 0x02,
  52 };
  53
  54 #pragma pack(push,1)
  55 struct ui_vert
  56 {
  57    ui_px co[2];
  58    u16 uv[2];
  59    u32 colour;
  60 };
  61 #pragma pack(pop)
  62
  63 enum ui_scheme_colour{
  64    k_ui_bg      = 0,
  65    k_ui_fg      = 8,
  66    k_ui_hue     = 16,
  67    k_ui_red     = 16,
  68    k_ui_orange,
  69    k_ui_yellow,
  70    k_ui_green,
  71    k_ui_aqua,
  72    k_ui_blue,
  73    k_ui_purple,
  74    k_ui_gray,
  75    k_ui_brighter = 8
  76 };
  77
  78 enum ui_shader {
  79    k_ui_shader_colour,
  80    k_ui_shader_image,
  81    k_ui_shader_hsv,
  82 };
  83
  84 extern ui_px k_ui_widget_height,
  85              k_ui_scale,
  86              k_ui_padding;
  87
  88 typedef u32 ui_scheme[8*4];
  89
  90 #define UI_RGB( STDHEX )          0xff000000       |\
  91                          ((STDHEX&0x000000ff)<<16) |\
  92                          ((STDHEX&0x0000ff00)    ) |\
  93                          ((STDHEX&0x00ff0000)>>16)
  94
  95 #define UI_TEXTBOX_MULTILINE 0x1
  96 #define UI_TEXTBOX_WRAP      0x2
  97 #define UI_TEXTBOX_AUTOFOCUS 0x4
  98
  99 #define UI_MODAL_OK        0x0
 100 #define UI_MODAL_GOOD      0x1
 101 #define UI_MODAL_BAD       0x2
 102 #define UI_MODAL_WARN      0x3
 103 #define UI_MODAL_TYPE_BITS 0x3
 104
 105 #define UI_MOUSE_LEFT   (SDL_BUTTON(SDL_BUTTON_LEFT))
 106 #define UI_MOUSE_RIGHT  (SDL_BUTTON(SDL_BUTTON_RIGHT))
 107 #define UI_MOUSE_MIDDLE (SDL_BUTTON(SDL_BUTTON_MIDDLE))
 108
 109 #define UI_TOP 0x1
 110 #define UI_LEFT 0x2
 111 #define UI_BOTTOM 0x4
 112 #define UI_RIGHT 0x8
 113
 114 struct vg_imgui
 115 {
 116    struct ui_vert *vertex_buffer;
 117    u16            *indice_buffer;
 118         u32 max_verts, max_indices,
 119        cur_vert,  cur_indice,
 120        vert_start, indice_start;
 121
 122    union {
 123    void *focused_control_id; /* uses the memory location of various locking
 124                                 controls as an id */
 125    char *textbuf;
 126    i32 *ptr_enum;
 127    };
 128
 129    u32 focused_control_hit;
 130    enum ui_control_type{
 131       k_ui_control_none,
 132       k_ui_control_textbox,
 133       k_ui_control_enum,
 134                 k_ui_control_modal
 135    }
 136    focused_control_type;
 137
 138    union{ /* controls that can be focused */
 139       struct ui_textbuf{
 140          int cursor_user, cursor_pos;
 141          u32 len;
 142          u32 flags;
 143
 144          struct ui_textbox_callbacks{
 145             void (*enter)( char *, u32 ),
 146                  (*up)( char *, u32 ),
 147                  (*down)( char *, u32 ),
 148                  (*change)( char *, u32 ),
 149                  (*escape)( void );
 150          }
 151          callbacks;
 152       }
 153       textbox;
 154
 155       struct ui_enum{
 156          struct ui_enum_opt{
 157             i32 value;
 158             const char *alias;
 159          }
 160          *options;
 161          u32 option_count;
 162          ui_rect rect;
 163       }
 164       _enum;
 165    };
 166
 167         struct ui_modal{
 168                 const char *message;
 169                 u32 options;
 170
 171                 struct ui_modal_callbacks{
 172                         void (*close)(u32);
 173                 }
 174                 callbacks;
 175         }
 176    modal;
 177
 178         GLuint tex_glyphs, vao, vbo, ebo, tex_bg;
 179    v2f bg_inverse_ratio;
 180
 181         ui_px mouse[2], mouse_delta[2], mouse_click[2];
 182    u32 mouse_state[2];
 183    u32 ignore_input_frames;
 184    bool mouse_pos_overriden;
 185    int wants_mouse;
 186
 187    ui_rect click_fader, click_fader_end;
 188    float click_fade_opacity;
 189    f32 frosting;
 190
 191    ui_scheme scheme;
 192    const vg_font_face *font;
 193    v2f inverse_font_sheet;
 194
 195    enum ui_cursor{
 196       k_ui_cursor_default,
 197       k_ui_cursor_ibeam,
 198       k_ui_cursor_hand,
 199       k_ui_cursor_max
 200    }
 201    cursor;
 202
 203    SDL_Cursor *cursor_map[ k_ui_cursor_max ];
 204    v4f colour;
 205
 206    f32 hue; /* lol this sucks */
 207 }
 208 extern vg_ui;
 209
 210 enum ui_button_state {
 211    k_ui_button_none            = 0x0,
 212    k_ui_button_click           = 0x1,
 213    k_ui_button_holding_inside  = 0x2,
 214    k_ui_button_holding_outside = 0x4,
 215    k_ui_button_hover           = 0x8
 216 };
 217
 218 /* TODO: docu.. */
 219
 220 void vg_ui_init(void);
 221 void rect_copy( ui_rect a, ui_rect b );
 222 void ui_flush( enum ui_shader shader, f32 w, f32 h );
 223 struct ui_vert *ui_fill_rect( ui_rect rect, u32 colour, ui_px uv[4] );
 224 struct ui_vert *ui_fill( ui_rect rect, u32 colour );
 225 void ui_outline( ui_rect rect, ui_px thickness, u32 colour, u32 mask );
 226 void ui_split( ui_rect rect, enum ui_axis other, ui_px width, ui_px gap,
 227                ui_rect l, ui_rect r );
 228 void ui_rect_center( ui_rect parent, ui_rect rect );
 229 void ui_fit_item( ui_rect rect, ui_px size[2], ui_rect d );
 230 void ui_split_ratio( ui_rect rect, enum ui_axis dir, float ratio,
 231                      ui_px gap, ui_rect l, ui_rect r );
 232 void ui_rect_pad( ui_rect rect, ui_px pad[2] );
 233 ui_px ui_text_line_width( const char *str );
 234 ui_px ui_text_string_height( const char *str );
 235 ui_px ui_text_aligned_x( const char *str, ui_rect rect, ui_px scale,
 236                          enum ui_align align );
 237 int ui_clip( ui_rect parent, ui_rect child, ui_rect clipped );
 238 int ui_inside_rect( ui_rect rect, ui_px co[2] );
 239 int ui_click_down( u32 mask );
 240 int ui_clicking( u32 mask );
 241 int ui_click_up( u32 mask );
 242 void ui_set_mouse_pos( ui_px x, ui_px y );
 243 void ui_prerender(void);
 244 u32 ui_colour( enum ui_scheme_colour id );
 245
 246 /* get an appropriately contrasting colour given the base */
 247 u32 ui_colourcont( enum ui_scheme_colour id );
 248
 249 void ui_hex_to_norm( u32 hex, v4f norm );
 250 u32 v4f_u32_colour( v4f colour );
 251
 252 u32 ui_opacity( u32 colour, f32 opacity );
 253 void ui_font_face( vg_font_face *ff );
 254 u32 ui_ntext( ui_rect rect, const char *str, u32 len, ui_px scale,
 255               enum ui_align align, u32 colour );
 256 u32 ui_text( ui_rect rect, const char *str, ui_px scale,
 257              enum ui_align align, u32 colour );
 258 void ui_panel( ui_rect in_rect, ui_rect out_panel );
 259 void ui_label( ui_rect rect, const char *text, ui_px size,
 260                ui_px gap, ui_rect r );
 261 void ui_standard_widget( ui_rect inout_panel, ui_rect out_rect, ui_px count );
 262 void ui_info( ui_rect inout_panel, const char *text );
 263 void ui_image( ui_rect rect, GLuint image );
 264 void ui_defocus_all(void);
 265
 266 enum ui_button_state ui_button_base( ui_rect rect );
 267 enum ui_button_state ui_colourbutton( ui_rect rect,
 268                                       enum ui_scheme_colour colour,
 269                                       enum ui_scheme_colour hover_colour,
 270                                       enum ui_scheme_colour hi_colour );
 271 enum ui_button_state ui_colourbutton_text(
 272       ui_rect rect, const char *string, ui_px scale,
 273       enum ui_scheme_colour colour );
 274 enum ui_button_state ui_button_text( ui_rect rect,
 275                                      const char *string, ui_px scale );
 276 enum ui_button_state ui_button( ui_rect inout_panel, const char *string );
 277
 278 void ui_postrender(void);
 279
 280 int ui_checkbox( ui_rect inout_panel, const char *str_label, i32 *data );
 281 void ui_enum( ui_rect inout_panel, const char *str_label,
 282               struct ui_enum_opt *options, u32 len, i32 *value );
 283 bool ui_slider( ui_rect inout_panel, const char *str_label,
 284                 f32 min, f32 max, f32 *value, const char *format );
 285 void ui_colourpicker( ui_rect inout_panel, const char *str_label, v4f value );
 286 int ui_textbox( ui_rect inout_panel, const char *label,
 287                 char *buf, u32 len, u32 lines, u32 flags,
 288                 struct ui_textbox_callbacks *callbacks );
 289 void ui_tabs( ui_rect inout_panel, ui_rect out_content_panel,
 290               const char **titles, u32 count, i32 *page );
 291 void ui_start_modal( const char *message, u32 options );
 292 void ui_proc_key( SDL_Keysym ev );
 293 void ui_proc_utf8( const char *text );
 294 void ui_dev_colourview(void);
 295
 296 void _ui_textbox_move_cursor( int *cursor0, int *cursor1,
 297                               int dir, int snap_together );
 298 int _ui_textbox_delete_char( int direction );
 299 void _ui_textbox_put_char( char c );
 300 void _ui_textbox_up(void);
 301 void _ui_textbox_left(void);
 302 void _ui_textbox_left_select(void);
 303 void _ui_textbox_down(void);
 304 void _ui_textbox_right_select(void);
 305 void _ui_textbox_right(void);
 306 void _ui_textbox_backspace(void);
 307 void _ui_textbox_delete(void);
 308 void _ui_textbox_home_select(void);
 309 void _ui_textbox_home(void);
 310 void _ui_textbox_end_select(void);
 311 void _ui_textbox_end(void);
 312 void _ui_textbox_select_all(void);
 313 void _ui_textbox_cut(void);
 314 void _ui_textbox_enter(void);