vg/vg_ui.h

   1 // Copyright (C) 2021 Harry Godden (hgn) - All Rights Reserved
   2 /*
   3
   4         Concurrent UI buffer system
   5         Coordinate space:
   6
   7    0,0 --- +(res:x)
   8          |
   9          |
  10          |
  11 +(res:y)
  12
  13 */
  14
  15 SHADER_DEFINE( shader_ui,
  16
  17         // VERTEX
  18         "layout (location=0) in vec2 a_co;"                     // i16, i16, .. ?
  19         "layout (location=1) in vec2 a_uv;"                     // i8, i8
  20         "layout (location=2) in vec4 a_colour;" // u32
  21         "uniform mat3 uPv;"
  22         ""
  23         "out vec2 aTexCoords;"
  24         "out vec4 aColour;"
  25         ""
  26         "void main()"
  27         "{"
  28                 "gl_Position = vec4( uPv * vec3( a_co, 1.0 ), 1.0 );"
  29                 "aTexCoords = a_uv * 0.01388888888;"
  30                 "aColour = a_colour;"
  31         "}",
  32
  33         // FRAGMENT
  34         "uniform sampler2D uTexGlyphs;"
  35         "out vec4 FragColor;"
  36         ""
  37         "in vec2 aTexCoords;"
  38         "in vec4 aColour;"
  39         ""
  40         "void main()"
  41         "{"
  42                 "vec4 glyph = texture( uTexGlyphs, aTexCoords );"
  43                 "FragColor = aColour * vec4( 1.0, 1.0, 1.0, glyph.r );"
  44         "}"
  45         ,
  46         UNIFORMS({ "uPv", "uTexGlyphs" })
  47 )
  48
  49 #define UI_AUTO_FILL 0
  50
  51 // Types
  52 // ================================================================
  53 typedef i16                             ui_px;
  54 typedef u32                             ui_colour;
  55 typedef ui_px                           ui_rect[4];
  56 typedef struct ui_ctx   ui_ctx;
  57
  58 #pragma pack(push,1)
  59 struct ui_vert
  60 {
  61         ui_px co[2];
  62         u8 uv[2];
  63         u32 colour;
  64 };
  65 #pragma pack(pop)
  66
  67 struct ui_ctx
  68 {
  69         ui_px padding;
  70
  71         struct ui_qnode
  72         {
  73                 ui_rect                 rect;
  74                 ui_colour       colour;
  75                 int                     mouse_over;
  76                 int                     capture_id;
  77         }
  78         stack[ 32 ];
  79
  80         struct ui_vert *verts;
  81         u32 num_verts;
  82         u16 *indices;
  83         u32 num_indices;
  84
  85         ui_rect cursor;
  86         u32 stack_count;
  87         u32 capture_mouse_id;
  88         int capture_lock;
  89         u32 id_base;
  90
  91         // User input
  92         ui_px mouse[2];
  93         int click_state;        // 0: released, 1: on down, 2: pressed, 3: on release
  94 };
  95
  96 // Opengl
  97 GLuint ui_glyph_texture;
  98 GLuint ui_vao;
  99 GLuint ui_vbo;
 100 GLuint ui_ebo;
 101
 102
 103
 104 #define UI_BUFFER_SIZE 30000
 105 #define UI_INDEX_SIZE 20000
 106
 107 static void ui_glyphs_load( u32 *compressed )
 108 {
 109         u32 pixels = 0, total = 72*72, data = 0;
 110         u8 *image = malloc( total );
 111
 112         while( pixels < total )
 113         {
 114                 for( int b = 31; b >= 0; b-- )
 115                 {
 116                         image[ pixels ++ ] = (compressed[data] & (0x1 << b))? 0xff: 0x00;
 117
 118                         if( pixels >= total )
 119                         {
 120                                 total = 0;
 121                                 break;
 122                         }
 123                 }
 124                 data++;
 125         }
 126
 127         for( int j = 0; j < 70; j ++ )
 128         {
 129                 for( int i = 0; i < 70; i ++ )
 130                         printf( "%s",image[j*72+i]?"#":" " );
 131                 printf( "\n" );
 132         }
 133
 134         glGenTextures( 1, &ui_glyph_texture );
 135         glBindTexture( GL_TEXTURE_2D, ui_glyph_texture );
 136
 137         glTexImage2D( GL_TEXTURE_2D, 0, GL_R8, 72, 72, 0, GL_RED, GL_UNSIGNED_BYTE, image );
 138
 139         vg_tex2d_clamp();
 140         vg_tex2d_nearest();
 141
 142         free( image );
 143 }
 144
 145 static void ui_default_init(void)
 146 {
 147         ui_glyphs_load( (u32[]){
 148                 #include "fonts/weiholmir.h"
 149         });
 150
 151         SHADER_INIT( shader_ui );
 152
 153         // Generate the buffer we are gonna be drawing to
 154         glGenVertexArrays(1, &ui_vao);
 155         glGenBuffers( 1, &ui_vbo );
 156         glGenBuffers( 1, &ui_ebo );
 157         glBindVertexArray( ui_vao );
 158
 159         glBindBuffer( GL_ARRAY_BUFFER, ui_vbo );
 160
 161         glBufferData( GL_ARRAY_BUFFER, UI_BUFFER_SIZE * sizeof( struct ui_vert ), NULL, GL_DYNAMIC_DRAW );
 162         glBindVertexArray( ui_vao );
 163
 164         glBindBuffer( GL_ELEMENT_ARRAY_BUFFER, ui_ebo );
 165         glBufferData( GL_ELEMENT_ARRAY_BUFFER, UI_INDEX_SIZE * sizeof( u16 ), NULL, GL_DYNAMIC_DRAW );
 166
 167         // XY
 168         glVertexAttribPointer( 0, 2, GL_UNSIGNED_SHORT, GL_FALSE, sizeof( struct ui_vert ), (void *)offsetof( struct ui_vert, co ) );
 169         glEnableVertexAttribArray( 0 );
 170
 171         // UV
 172         glVertexAttribPointer( 1, 2, GL_UNSIGNED_BYTE, GL_FALSE, sizeof( struct ui_vert ), (void *)offsetof( struct ui_vert, uv ) );
 173         glEnableVertexAttribArray( 1 );
 174
 175         // COLOUR
 176         glVertexAttribPointer( 2, 4, GL_UNSIGNED_BYTE, GL_TRUE, sizeof( struct ui_vert ), (void *)offsetof( struct ui_vert, colour ) );
 177         glEnableVertexAttribArray( 2 );
 178 }
 179
 180 static void ui_default_free(void)
 181 {
 182         glDeleteTextures( 1, &ui_glyph_texture );
 183
 184         glDeleteVertexArrays( 1, &ui_vao );
 185         glDeleteBuffers( 1, &ui_vbo );
 186         glDeleteBuffers( 1, &ui_ebo );
 187 }
 188
 189 static void ui_draw( ui_ctx *ctx )
 190 {
 191         glBindVertexArray( ui_vao );
 192
 193         glBindBuffer( GL_ARRAY_BUFFER, ui_vbo );
 194         glBufferSubData( GL_ARRAY_BUFFER, 0, ctx->num_verts * sizeof( struct ui_vert ), ctx->verts );
 195
 196         glBindBuffer( GL_ELEMENT_ARRAY_BUFFER, ui_ebo );
 197         glBufferSubData( GL_ELEMENT_ARRAY_BUFFER, 0, ctx->num_indices * sizeof( u16 ), ctx->indices );
 198
 199         glEnable(GL_BLEND);
 200         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 201         glBlendEquation(GL_FUNC_ADD);
 202
 203         SHADER_USE( shader_ui );
 204
 205         m3x3f view = M3X3_IDENTITY;
 206         m3x3_translate( view, (v3f){ -1.0f, 1.0f, 0.0f } );
 207         m3x3_scale( view, (v3f){ 1.0f/((float)vg_window_x*0.5f), -1.0f/((float)vg_window_y*0.5f), 1.0f } );
 208         glUniformMatrix3fv( SHADER_UNIFORM( shader_ui, "uPv" ), 1, GL_FALSE, (float *)view );
 209
 210         glActiveTexture( GL_TEXTURE0 );
 211         glBindTexture( GL_TEXTURE_2D, ui_glyph_texture );
 212         glUniform1i( SHADER_UNIFORM( shader_ui, "uTexGlyphs" ), 0 );
 213
 214         glDrawElements( GL_TRIANGLES, ctx->num_indices, GL_UNSIGNED_SHORT, (void*)(0) );
 215
 216         //vg_info( "Verts: %u, Indices: %u\n", ctx->num_verts, ctx->num_indices );
 217
 218         glDisable(GL_BLEND);
 219 }
 220
 221 // Rect controls
 222 // ==========================================================
 223
 224 static void ui_rect_copy( ui_rect src, ui_rect dst )
 225 {
 226         dst[0] = src[0];
 227         dst[1] = src[1];
 228         dst[2] = src[2];
 229         dst[3] = src[3];
 230 }
 231
 232 static void ui_rect_pad( ui_ctx *ctx, ui_rect rect, ui_px pad )
 233 {
 234         rect[0] += pad;
 235         rect[1] += pad;
 236         rect[2] -= pad*2;
 237         rect[3] -= pad*2;
 238 }
 239
 240 static void ui_vis_rect( ui_rect rect, u32 colour )
 241 {
 242         v2f p0;
 243         v2f p1;
 244
 245         p0[0] = rect[0];
 246         p0[1] = rect[1];
 247         p1[0] = rect[0]+rect[2];
 248         p1[1] = rect[1]+rect[3];
 249
 250         vg_line( p0, (v2f){p1[0],p0[1]}, colour );
 251         vg_line( (v2f){p1[0],p0[1]}, p1, colour );
 252         vg_line( p1, (v2f){p0[0],p1[1]}, colour );
 253         vg_line( (v2f){p0[0],p1[1]}, p0, colour );
 254 }
 255
 256 static void ui_new_node( ui_ctx *ctx )
 257 {
 258         if( ctx->stack_count == vg_list_size( ctx->stack ) )
 259                 vg_exiterr( "[UI] Stack overflow while creating box!" );
 260
 261         struct ui_qnode *parent = &ctx->stack[ ctx->stack_count-1 ];
 262         struct ui_qnode *node = &ctx->stack[ ctx->stack_count++ ];
 263         ui_rect_copy( ctx->cursor, node->rect );
 264
 265         if( parent->mouse_over )
 266         {
 267                 if( ctx->mouse[0] >= node->rect[0] && ctx->mouse[0] <= node->rect[0]+node->rect[2] &&
 268                          ctx->mouse[1] >= node->rect[1] && ctx->mouse[1] <= node->rect[1]+node->rect[3] )
 269                         node->mouse_over = 1;
 270                 else
 271                         node->mouse_over = 0;
 272         }
 273         else
 274         {
 275                 node->mouse_over = 0;
 276         }
 277 }
 278
 279 static int ui_hasmouse( ui_ctx *ctx )
 280 {
 281         struct ui_qnode *node = &ctx->stack[ ctx->stack_count-1 ];
 282         return (node->mouse_over && (node->capture_id == ctx->capture_mouse_id));
 283 }
 284
 285 static void ui_end( ui_ctx *ctx )
 286 {
 287         struct ui_qnode *node = &ctx->stack[ --ctx->stack_count ];
 288
 289         ui_rect_copy( node->rect, ctx->cursor );
 290         ui_vis_rect( ctx->cursor, (node->mouse_over && (node->capture_id == ctx->capture_mouse_id))? 0xffff0000: 0xff0000ff );
 291 }
 292
 293 static void ui_end_down( ui_ctx *ctx )
 294 {
 295         ui_px height = ctx->stack[ ctx->stack_count-1 ].rect[3];
 296         ui_end( ctx );
 297         ctx->cursor[1] += height;
 298 }
 299
 300 static void ui_end_right( ui_ctx *ctx )
 301 {
 302         ui_px width = ctx->stack[ ctx->stack_count-1 ].rect[2];
 303         ui_end( ctx );
 304         ctx->cursor[0] += width;
 305 }
 306
 307 static void ui_align_right( ui_ctx *ctx )
 308 {
 309         struct ui_qnode *node = &ctx->stack[ ctx->stack_count-1 ];
 310         ctx->cursor[0] = node->rect[0] + node->rect[2] - ctx->cursor[2];
 311 }
 312
 313 static void ui_align_top( ui_ctx *ctx )
 314 {
 315         struct ui_qnode *node = &ctx->stack[ ctx->stack_count-1 ];
 316         ctx->cursor[1] = node->rect[1] + node->rect[3] - ctx->cursor[3];
 317 }
 318
 319 static void ui_clamp_rect( ui_rect parent, ui_rect dest )
 320 {
 321         dest[0] = vg_min( parent[0] + parent[2] - dest[2], dest[0] );
 322         dest[1] = vg_min( parent[1] + parent[3] - dest[3], dest[1] );
 323         dest[0] = vg_max( parent[0], dest[0] );
 324         dest[1] = vg_max( parent[1], dest[1] );
 325 }
 326
 327 static u32 ui_group_id( ui_ctx *ctx, u32 lesser_unique )
 328 {
 329         return ctx->id_base | lesser_unique;
 330 }
 331
 332 static void ui_capture_mouse( ui_ctx *ctx, u32 id )
 333 {
 334         u32 group_uid = ui_group_id(ctx,id);
 335
 336         struct ui_qnode *node = &ctx->stack[ ctx->stack_count-1 ];
 337         node->capture_id = group_uid;
 338
 339         if( !ctx->capture_lock && node->mouse_over )
 340         {
 341                 ctx->capture_mouse_id = group_uid;
 342         }
 343 }
 344
 345 static void ui_fill_rect( ui_ctx *ctx, ui_rect rect, u32 colour )
 346 {
 347         ui_px uv[2];
 348         uv[0] = 66;
 349         uv[1] = 66;
 350
 351         struct ui_vert *vertices = &ctx->verts[ ctx->num_verts ];
 352         vertices[0].co[0] = rect[0];
 353         vertices[0].co[1] = rect[1];
 354         vertices[0].uv[0] = uv[0];
 355         vertices[0].uv[1] = uv[1];
 356         vertices[0].colour = colour;
 357         vertices[1].co[0] = rect[0]+rect[2];
 358         vertices[1].co[1] = rect[1];
 359         vertices[1].uv[0] = uv[0];
 360         vertices[1].uv[1] = uv[1];
 361         vertices[1].colour = colour;
 362         vertices[2].co[0] = rect[0]+rect[2];
 363         vertices[2].co[1] = rect[1]+rect[3];
 364         vertices[2].uv[0] = uv[0];
 365         vertices[2].uv[1] = uv[1];
 366         vertices[2].colour = colour;
 367         vertices[3].co[0] = rect[0];
 368         vertices[3].co[1] = rect[1]+rect[3];
 369         vertices[3].uv[0] = uv[0];
 370         vertices[3].uv[1] = uv[1];
 371         vertices[3].colour = colour;
 372         u16 ind_start = ctx->num_verts;
 373         u16 *indices = &ctx->indices[ ctx->num_indices ];
 374
 375         indices[0] = ind_start+0;
 376         indices[1] = ind_start+2;
 377         indices[2] = ind_start+1;
 378
 379         indices[3] = ind_start+0;
 380         indices[4] = ind_start+3;
 381         indices[5] = ind_start+2;
 382
 383         ctx->num_indices += 6;
 384         ctx->num_verts += 4;
 385 }
 386
 387 static void ui_text( ui_ctx *ctx, const char *str, ui_px scale, int alignment )
 388 {
 389         ui_rect text_cursor;
 390
 391         text_cursor[0] = ctx->cursor[0];
 392         text_cursor[1] = ctx->cursor[1];
 393         text_cursor[2] = 7*scale;
 394         text_cursor[3] = 7*scale;
 395
 396         const char *_c = str;
 397         char c;
 398         while( (c = *(_c ++)) )
 399         {
 400                 if( c == '\n' )
 401                 {
 402                         text_cursor[1] += 10*scale;
 403                         text_cursor[0] = ctx->cursor[0];
 404                         continue;
 405                 }
 406                 else if( c >= 33 && c <= 126 )
 407                 {
 408                         u8 glyph_base[2];
 409                         u8 glyph_index = c - 32;
 410                         glyph_base[0] = glyph_index%10;
 411                         glyph_base[1] = (glyph_index-glyph_base[0])/10;
 412
 413                         glyph_base[0] *= 7;
 414                         glyph_base[1] *= 7;
 415
 416
 417                         struct ui_vert *vertices = &ctx->verts[ctx->num_verts];
 418                         vertices[0].co[0] = text_cursor[0];
 419                         vertices[0].co[1] = text_cursor[1];
 420                         vertices[0].uv[0] = glyph_base[0];
 421                         vertices[0].uv[1] = glyph_base[1];
 422                         vertices[0].colour = 0xffffffff;
 423
 424                         vertices[1].co[0] = text_cursor[0]+text_cursor[2];
 425                         vertices[1].co[1] = text_cursor[1];
 426                         vertices[1].uv[0] = glyph_base[0]+7;
 427                         vertices[1].uv[1] = glyph_base[1];
 428                         vertices[1].colour = 0xffffffff;
 429
 430                         vertices[2].co[0] = text_cursor[0]+text_cursor[2];
 431                         vertices[2].co[1] = text_cursor[1]+text_cursor[3];
 432                         vertices[2].uv[0] = glyph_base[0]+7;
 433                         vertices[2].uv[1] = glyph_base[1]+7;
 434                         vertices[2].colour = 0xffffffff;
 435
 436                         vertices[3].co[0] = text_cursor[0];
 437                         vertices[3].co[1] = text_cursor[1]+text_cursor[3];
 438                         vertices[3].uv[0] = glyph_base[0];
 439                         vertices[3].uv[1] = glyph_base[1]+7;
 440                         vertices[3].colour = 0xffffffff;
 441
 442                         u16 ind_start = ctx->num_verts;
 443                         u16 *indices = &ctx->indices[ ctx->num_indices ];
 444
 445                         indices[0] = ind_start+0;
 446                         indices[1] = ind_start+2;
 447                         indices[2] = ind_start+1;
 448
 449                         indices[3] = ind_start+0;
 450                         indices[4] = ind_start+3;
 451                         indices[5] = ind_start+2;
 452
 453                         ctx->num_indices += 6;
 454                         ctx->num_verts += 4;
 455                 }
 456
 457                 text_cursor[0] += 6*scale;
 458         }
 459 }
 460
 461 // API control
 462 // ====================================================================
 463
 464 static void ui_begin( ui_ctx *ctx, ui_px res_x, ui_px res_y )
 465 {
 466         ctx->cursor[0] = 0;
 467         ctx->cursor[1] = 0;
 468         ctx->cursor[2] = res_x;
 469         ctx->cursor[3] = res_y;
 470
 471         ui_rect_copy( ctx->cursor, ctx->stack[0].rect );
 472         ctx->stack[0].mouse_over = 1;
 473
 474         ctx->stack_count = 1;
 475
 476         ctx->num_verts = 0;
 477         ctx->num_indices = 0;
 478 }
 479
 480 static void ui_resolve( ui_ctx *ctx )
 481 {
 482         if( ctx->stack_count-1 )
 483                 vg_exiterr( "[UI] Mismatched node create/drestroy!" );
 484
 485         if( ctx->click_state == 3 || ctx->click_state == 0 )
 486         {
 487                 ctx->capture_lock = 0;
 488         }
 489 }
 490
 491 // User Input piping
 492 // ====================================================================
 493
 494 static void ui_set_mouse( ui_ctx *ctx, int x, int y, int click_state )
 495 {
 496         ctx->mouse[0] = x;
 497         ctx->mouse[1] = y;
 498
 499         ctx->click_state = click_state;
 500 }
 501
 502 // High level controls
 503 // ====================================================================
 504
 505 struct ui_window
 506 {
 507         const char *title;
 508         ui_rect transform;
 509
 510         int     drag;
 511         ui_px drag_offset[2];
 512 };
 513
 514 static int ui_button( ui_ctx *ctx, u32 id )
 515 {
 516         ui_new_node( ctx );
 517         {
 518                 ui_capture_mouse( ctx, id );
 519
 520                 if( ui_hasmouse(ctx) )
 521                 {
 522                         if( ctx->click_state == 1 )
 523                                 ctx->capture_lock = 1;
 524                         else if( ctx->capture_lock && ctx->click_state == 3 )
 525                         {
 526                                 return 1;
 527                         }
 528                 }
 529         }
 530
 531         return 0;
 532 }
 533
 534 static int ui_window( ui_ctx *ctx, struct ui_window *window, u32 control_group )
 535 {
 536         ctx->id_base = control_group << 16;
 537
 538         if( window->drag )
 539         {
 540                 window->transform[0] = ctx->mouse[0]+window->drag_offset[0];
 541                 window->transform[1] = ctx->mouse[1]+window->drag_offset[1];
 542
 543                 ui_clamp_rect( ctx->stack[0].rect, window->transform );
 544
 545                 if( ctx->click_state == 0 || ctx->click_state == 3 )
 546                 {
 547                         window->drag = 0;
 548                 }
 549         }
 550
 551         ui_rect_copy( window->transform, ctx->cursor );
 552
 553         ui_new_node( ctx );
 554         {
 555                 ui_capture_mouse( ctx, __COUNTER__ );
 556
 557                 ui_fill_rect( ctx, ctx->cursor, 0xff333333 );
 558
 559                 // Drag bar
 560                 ctx->cursor[3] = 25;
 561                 ui_new_node( ctx );
 562                 {
 563                         ui_capture_mouse( ctx, __COUNTER__ );
 564
 565                         ui_fill_rect( ctx, ctx->cursor, 0xff555555 );
 566
 567                         // title..
 568                         ctx->cursor[0] += 2;
 569                         ctx->cursor[1] += 2;
 570                         ui_text( ctx, window->title, 2, 0 );
 571
 572                         // Close button
 573                         ctx->cursor[3] = 25;
 574                         ctx->cursor[2] = 25;
 575                         ui_align_right( ctx );
 576                         ui_align_top( ctx );
 577                         ui_rect_pad( ctx, ctx->cursor, 4 );
 578
 579                         if( ui_button( ctx, __COUNTER__ ) )
 580                         {
 581                                 vg_info( "Click clacked\n" );
 582                         }
 583                         ui_end( ctx );
 584
 585                         if( ui_hasmouse( ctx ) )
 586                         {
 587                                 // start drag
 588                                 if( ctx->click_state == 1 )
 589                                 {
 590                                         window->drag = 1;
 591                                         window->drag_offset[0] = window->transform[0]-ctx->mouse[0];
 592                                         window->drag_offset[1] = window->transform[1]-ctx->mouse[1];
 593                                 }
 594                         }
 595                 }
 596                 ui_end_down( ctx );
 597         }
 598
 599         return 1;
 600 }
 601
 602 ui_ctx test_ctx = { .padding = 8 };
 603
 604 static void ui_test_init(void)
 605 {
 606         test_ctx.verts = (struct ui_vert *)malloc( UI_BUFFER_SIZE * sizeof(struct ui_vert) );
 607         test_ctx.indices = (u16*)malloc( UI_INDEX_SIZE * sizeof(u16) );
 608 }
 609
 610 static void ui_test_free(void)
 611 {
 612         free( test_ctx.verts );
 613         free( test_ctx.indices );
 614 }
 615
 616 static void ui_test(void)
 617 {
 618         /*
 619                 +------------------------------------------------------+
 620                 | Central Market                                    [x]|
 621                 +------+--------------+-+------------------------------+
 622                 | Buy  | Balance      |#| [filters] [favorites]        |
 623                 | <>_  | () 2,356     |#|----------------------------+-+
 624                 |------|--------------|#| [] potion of madness     4 |#|
 625                 | Sell | \ Main sword |#|----------------------------|#|
 626                 | _*^  |--------------|#| [] Balance of time      23 | |
 627                 |------| * Side arm   |#|----------------------------| |
 628                 | 235  |--------------| | [] Strength          5,300 | |
 629                 |      | () Sheild    | |----------------------------| |
 630                 |      |--------------| | [] Bewilder          2,126 | |
 631                 |      [ & Spells     ] |----------------------------| |
 632                 |      |--------------| | [] Eternal flames        6 | |
 633                 +------+--------------+-+----------------------------+-+
 634         */
 635
 636         ui_begin( &test_ctx, vg_window_x, vg_window_y );
 637
 638         // TODO: Find a more elegent form for this
 639         int mouse_state = 0;
 640         if( vg_get_button( "primary" ) ) mouse_state = 2;
 641         if( vg_get_button_down( "primary" ) ) mouse_state = 1;
 642         if( vg_get_button_up( "primary" ) ) mouse_state = 3;
 643
 644         ui_set_mouse( &test_ctx, vg_mouse[0], vg_mouse[1], mouse_state );
 645
 646         static struct ui_window window =
 647         {
 648                 .transform = { 20, 20, 500, 350 },
 649                 .title = "Central Market"
 650         };
 651
 652         if( ui_window( &test_ctx, &window, __COUNTER__ ) )
 653         {
 654                 // Contents
 655                 ui_text( &test_ctx, "Just say anything, George, say what ever's natural,\nthe first thing that comes to your mind.\nTake that you mutated son-of-a-bitch.", 1, 0 );
 656         }
 657         ui_end( &test_ctx );
 658
 659         ui_resolve( &test_ctx );
 660
 661         m3x3f view = M3X3_IDENTITY;
 662         m3x3_translate( view, (v3f){ -1.0f, 1.0f, 0.0f } );
 663         m3x3_scale( view, (v3f){ 1.0f/((float)vg_window_x*0.5f), -1.0f/((float)vg_window_y*0.5f), 1.0f } );
 664         vg_lines_drawall( (float*)view );
 665
 666         ui_draw( &test_ctx );
 667 }