src/vg/vg_ui.h

   1 /* Copyright (C) 2021-2022 Harry Godden (hgn) - All Rights Reserved */
   2
   3 #ifndef VG_UI_H
   4 #define VG_UI_H
   5
   6 #include "vg/vg.h"
   7 #include "vg/vg_tex.h"
   8 #include "vg/vg_shader.h"
   9
  10 static struct vg_shader _shader_ui =
  11 {
  12    .name = "[vg] ui",
  13    .link = NULL,
  14    .vs =
  15    {
  16       .orig_file = NULL,
  17       .static_src =
  18         "layout (location=0) in vec2 a_co;"
  19         "layout (location=1) in vec2 a_uv;"
  20         "layout (location=2) in vec4 a_colour;"
  21         "layout (location=3) in vec4 a_clip;"
  22         "uniform mat3 uPv;"
  23         ""
  24         "out vec2 aTexCoords;"
  25         "out vec4 aColour;"
  26         "out vec2 aWsp;"
  27         "out vec4 aClip;"
  28         ""
  29         "void main()"
  30         "{"
  31                 "gl_Position = vec4( uPv * vec3( a_co, 1.0 ), 1.0 );"
  32                 "aTexCoords = a_uv * 0.0078125;"
  33                 "aColour = a_colour;"
  34
  35                 "aWsp = a_co;"
  36                 "aClip = a_clip;"
  37         "}",
  38    },
  39    .fs =
  40    {
  41       .orig_file = NULL,
  42       .static_src =
  43         "uniform sampler2D uTexGlyphs;"
  44         "out vec4 FragColor;"
  45         ""
  46         "in vec2 aTexCoords;"
  47         "in vec4 aColour;"
  48         ""
  49         "in vec2 aWsp;"
  50         "in vec4 aClip;"
  51         ""
  52         "void main()"
  53         "{"
  54                 "float clip_blend = step( aWsp.x, aClip.z ) *"
  55                          "step( aWsp.y, aClip.w ) *"
  56                          "step( aClip.x, aWsp.x ) *"
  57                          "step( aClip.y, aWsp.y ); "
  58
  59                 "vec4 glyph = vec4(1.0,1.0,1.0,1.0);"
  60
  61                 "if( aColour.a == 0.0 )"
  62                 "{"
  63                         "glyph = texture( uTexGlyphs, aTexCoords );"
  64                         "glyph.a = smoothstep( 0.47, 0.53, glyph.r );"
  65                 "}"
  66                 "else"
  67                 "{"
  68                         "glyph.a = aColour.a;"
  69                 "}"
  70
  71                 "FragColor = vec4( aColour.rgb, glyph.a*clip_blend );"
  72         "}"
  73    }
  74 };
  75
  76 typedef i16                             ui_px;
  77 typedef u32                             ui_colour;
  78 typedef ui_px                           ui_rect[4];
  79 typedef struct ui_colourset ui_colourset;
  80
  81 /* Relative to cursor p0 */
  82 enum ui_text_align
  83 {
  84    k_text_align_left = 0,
  85    k_text_align_right = 1,
  86    k_text_align_center = 2
  87 };
  88
  89 struct ui_colourset
  90 {
  91         union
  92         {
  93                 struct
  94                 {
  95                         ui_colour main;
  96                         ui_colour hover;
  97                         ui_colour active;
  98                 };
  99                 struct
 100                 {
 101                         ui_colour background;
 102                         ui_colour bar;
 103                         ui_colour bar_hover;
 104                 };
 105         };
 106 };
 107
 108 #pragma pack(push,1)
 109 struct ui_vert
 110 {
 111    ui_px co[2];
 112    u8 uv[2];
 113    u32 colour;
 114    ui_rect clip;
 115 };
 116 #pragma pack(pop)
 117
 118 struct
 119 {
 120         struct ui_qnode
 121         {
 122                 ui_rect                 rect;
 123                 ui_colour       colour;
 124                 int                     mouse_over;
 125                 int                     capture_id;
 126         }
 127         stack[ 32 ];
 128
 129    u32 control_id;
 130
 131    struct ui_vert *vertex_buffer;
 132    u16            *indice_buffer;
 133         u32 num_verts, num_indices;
 134
 135         ui_rect clipping;
 136         ui_rect cursor;
 137         u32 stack_count;
 138         u32 capture_mouse_id;
 139         int capture_lock;
 140
 141         /* User input */
 142         ui_px mouse[2];
 143         int click_state;        /* 0: released, 1: on down, 2: pressed, 3: on release */
 144
 145         ui_colourset *colours;
 146
 147         GLuint vao;
 148         GLuint vbo;
 149         GLuint ebo;
 150
 151         struct ui_image
 152         {
 153                 ui_rect rc;
 154                 GLuint image;
 155         }
 156         images[16];
 157         int image_count;
 158 }
 159 static vg_uictx;
 160
 161 #define UI_GLYPH_SPACING_X 9
 162
 163 static GLuint ui_glyph_texture = 0;
 164 static ui_colourset ui_default_colours = {
 165         .main = 0xff807373,
 166         .hover = 0xff918484,
 167         .active = 0xffad9f9e
 168 };
 169
 170 VG_STATIC void ui_init_context(void)
 171 {
 172    if( !vg_shader_compile( &_shader_ui ) )
 173       vg_fatal_exit_loop( "Failed to compile ui shader" );
 174
 175    /*
 176     * Vertex buffer
 177     * ----------------------------------------
 178     */
 179    u32 index_buffer_size = 20000,
 180             vertex_buffer_size = (index_buffer_size+(index_buffer_size/2));
 181
 182         /* Generate the buffer we are gonna be drawing to */
 183    glGenVertexArrays( 1, &vg_uictx.vao );
 184    glGenBuffers( 1, &vg_uictx.vbo );
 185    glGenBuffers( 1, &vg_uictx.ebo );
 186
 187    glBindVertexArray( vg_uictx.vao );
 188    glBindBuffer( GL_ARRAY_BUFFER, vg_uictx.vbo );
 189
 190    glBufferData( GL_ARRAY_BUFFER,
 191          vertex_buffer_size * sizeof( struct ui_vert ),
 192          NULL, GL_DYNAMIC_DRAW );
 193    glBindVertexArray( vg_uictx.vao );
 194
 195    glBindBuffer( GL_ELEMENT_ARRAY_BUFFER, vg_uictx.ebo );
 196    glBufferData( GL_ELEMENT_ARRAY_BUFFER,
 197          index_buffer_size * sizeof( u16 ), NULL, GL_DYNAMIC_DRAW );
 198
 199    VG_CHECK_GL_ERR();
 200
 201    /* Set pointers */
 202    u32 const stride = sizeof( struct ui_vert );
 203
 204    /* XY */
 205    glVertexAttribPointer( 0, 2, GL_SHORT, GL_FALSE,
 206          stride, (void *)offsetof( struct ui_vert, co ) );
 207    glEnableVertexAttribArray( 0 );
 208
 209    /* UV */
 210    glVertexAttribPointer( 1, 2, GL_UNSIGNED_BYTE, GL_FALSE,
 211          stride, (void *)offsetof( struct ui_vert, uv ) );
 212    glEnableVertexAttribArray( 1 );
 213
 214    /* COLOUR */
 215    glVertexAttribPointer( 2, 4, GL_UNSIGNED_BYTE, GL_TRUE, stride,
 216          (void *)offsetof( struct ui_vert, colour ) );
 217    glEnableVertexAttribArray( 2 );
 218
 219    /* CLIPPING */
 220    glVertexAttribPointer( 3, 4, GL_SHORT, GL_FALSE, stride,
 221          (void *)offsetof( struct ui_vert, clip ) );
 222    glEnableVertexAttribArray( 3 );
 223
 224    VG_CHECK_GL_ERR();
 225
 226         /* Alloc RAM default context */
 227    u32 vert_size = vertex_buffer_size*sizeof(struct ui_vert),
 228        inds_size = index_buffer_size *sizeof(u16);
 229
 230    vg_uictx.vertex_buffer =
 231       vg_create_linear_allocator(vg_mem.rtmemory,vert_size);
 232
 233    vg_uictx.indice_buffer =
 234       vg_create_linear_allocator(vg_mem.rtmemory,inds_size);
 235
 236    /* font
 237     * -----------------------------------------------------
 238     */
 239
 240         /* Load default font */
 241    u32 compressed[] = {
 242       #include "vg/vg_pxfont.h"
 243    };
 244
 245    u32 pixels = 0, total = 256*256, data = 0;
 246    u8 image[256*256];
 247
 248    while( pixels < total )
 249    {
 250       for( int b = 31; b >= 0; b-- )
 251       {
 252          image[ pixels ++ ] = (compressed[data] & (0x1 << b))? 0xff: 0x00;
 253
 254          if( pixels >= total )
 255          {
 256             total = 0;
 257             break;
 258          }
 259       }
 260       data++;
 261    }
 262
 263    glGenTextures( 1, &ui_glyph_texture );
 264    glBindTexture( GL_TEXTURE_2D, ui_glyph_texture );
 265    glTexImage2D( GL_TEXTURE_2D, 0, GL_R8, 256, 256, 0,
 266                  GL_RED, GL_UNSIGNED_BYTE, image );
 267
 268    VG_CHECK_GL_ERR();
 269    vg_tex2d_clamp();
 270    vg_tex2d_nearest();
 271 }
 272
 273 static struct ui_vert *ui_fill_rect_uv( ui_rect rect, u32 colour, ui_px uv[4] );
 274
 275 VG_STATIC void ui_draw( m3x3f view_override )
 276 {
 277         u32 num_indices_normal = vg_uictx.num_indices;
 278
 279         /* Append images to back of buffer */
 280         for( int i = 0; i < vg_uictx.image_count; i ++ )
 281    {
 282                 ui_fill_rect_uv( vg_uictx.images[i].rc, 0xffffffff,
 283                        (ui_px[4]){0,0,128,128} );
 284    }
 285
 286         glBindVertexArray( vg_uictx.vao );
 287
 288         glBindBuffer( GL_ARRAY_BUFFER, vg_uictx.vbo );
 289         glBufferSubData( GL_ARRAY_BUFFER, 0,
 290          vg_uictx.num_verts * sizeof( struct ui_vert ),
 291          vg_uictx.vertex_buffer );
 292
 293         glBindBuffer( GL_ELEMENT_ARRAY_BUFFER, vg_uictx.ebo );
 294         glBufferSubData( GL_ELEMENT_ARRAY_BUFFER, 0,
 295          vg_uictx.num_indices * sizeof( u16 ),
 296          vg_uictx.indice_buffer );
 297
 298         glEnable(GL_BLEND);
 299         glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 300         glBlendEquation(GL_FUNC_ADD);
 301
 302    glUseProgram( _shader_ui.id );
 303
 304         m3x3f view = M3X3_IDENTITY;
 305
 306         if( !view_override )
 307         {
 308                 view_override = view;
 309
 310                 m3x3_translate( view, (v3f){ -1.0f, 1.0f, 0.0f } );
 311                 m3x3_scale( view, (v3f){ 1.0f/((float)vg.window_x*0.5f),
 312                               -1.0f/((float)vg.window_y*0.5f), 1.0f } );
 313         }
 314
 315    /* TODO? */
 316         glUniformMatrix3fv( glGetUniformLocation( _shader_ui.id, "uPv" ), 1,
 317          GL_FALSE, (float *)view_override );
 318
 319         glActiveTexture( GL_TEXTURE0 );
 320         glBindTexture( GL_TEXTURE_2D, ui_glyph_texture );
 321         glUniform1i( glGetUniformLocation( _shader_ui.id, "uTexGlyphs" ), 0 );
 322
 323         glDrawElements( GL_TRIANGLES, num_indices_normal,
 324          GL_UNSIGNED_SHORT, (void*)(0) );
 325
 326         /* Draw image elements */
 327         for( int i = 0; i < vg_uictx.image_count; i ++ )
 328         {
 329                 struct ui_image *img = &vg_uictx.images[i];
 330
 331                 glBindTexture( GL_TEXTURE_2D, img->image );
 332                 glDrawElements( GL_TRIANGLES, 6, GL_UNSIGNED_SHORT,
 333             (void*)( (num_indices_normal + 6*i)*sizeof(u16) ) );
 334         }
 335
 336         glDisable(GL_BLEND);
 337 }
 338
 339 /*
 340  * Rect controls
 341  */
 342 VG_STATIC void ui_rect_copy( ui_rect src, ui_rect dst )
 343 {
 344         dst[0] = src[0];
 345         dst[1] = src[1];
 346         dst[2] = src[2];
 347         dst[3] = src[3];
 348 }
 349
 350 VG_STATIC void ui_rect_pad( ui_rect rect, ui_px pad )
 351 {
 352         rect[0] += pad;
 353         rect[1] += pad;
 354         rect[2] -= pad*2;
 355         rect[3] -= pad*2;
 356 }
 357
 358 /*
 359  * Stack control
 360  */
 361 static struct ui_qnode *ui_current(void)
 362 {
 363         return &vg_uictx.stack[ vg_uictx.stack_count-1 ];
 364 }
 365
 366 VG_STATIC void ui_new_node(void)
 367 {
 368         if( vg_uictx.stack_count == vg_list_size( vg_uictx.stack ) )
 369    {
 370       vg_error( "[UI] Stack overflow while creating box!" );
 371       return;
 372    }
 373
 374         struct ui_qnode *parent = &vg_uictx.stack[ vg_uictx.stack_count-1 ];
 375         struct ui_qnode *node = &vg_uictx.stack[ vg_uictx.stack_count++ ];
 376         ui_rect_copy( vg_uictx.cursor, node->rect );
 377
 378         if( parent->mouse_over )
 379         {
 380                 if( vg_uictx.mouse[0] >= node->rect[0] &&
 381           vg_uictx.mouse[0] < node->rect[0]+node->rect[2] &&
 382                          vg_uictx.mouse[1] >= node->rect[1] &&
 383           vg_uictx.mouse[1] < node->rect[1]+node->rect[3] )
 384                         node->mouse_over = 1;
 385                 else
 386                         node->mouse_over = 0;
 387         }
 388         else
 389         {
 390                 node->mouse_over = 0;
 391         }
 392 }
 393
 394 static int ui_hasmouse(void)
 395 {
 396         struct ui_qnode *node = ui_current();
 397         return (node->mouse_over && (node->capture_id == vg_uictx.capture_mouse_id));
 398 }
 399
 400 VG_STATIC void ui_end(void)
 401 {
 402         struct ui_qnode *node = &vg_uictx.stack[ --vg_uictx.stack_count ];
 403         ui_rect_copy( node->rect, vg_uictx.cursor );
 404 }
 405
 406 VG_STATIC void ui_end_down(void)
 407 {
 408         ui_px height = ui_current()->rect[3];
 409         ui_end();
 410         vg_uictx.cursor[1] += height;
 411 }
 412
 413 VG_STATIC void ui_end_right(void)
 414 {
 415         ui_px width = ui_current()->rect[2];
 416         ui_end();
 417         vg_uictx.cursor[0] += width;
 418 }
 419
 420 VG_STATIC void ui_fill_y(void)
 421 {
 422         struct ui_qnode *node = ui_current();
 423         vg_uictx.cursor[3] = node->rect[3] - (vg_uictx.cursor[1]-node->rect[1]);
 424 }
 425
 426 VG_STATIC void ui_fill_x(void)
 427 {
 428         struct ui_qnode *node = ui_current();
 429         vg_uictx.cursor[2] = node->rect[2] - (vg_uictx.cursor[0]-node->rect[0]);
 430 }
 431
 432 VG_STATIC void ui_align_bottom(void)
 433 {
 434         struct ui_qnode *node = ui_current();
 435         vg_uictx.cursor[1] = node->rect[1] + node->rect[3] - vg_uictx.cursor[3];
 436 }
 437
 438 VG_STATIC void ui_align_right(void)
 439 {
 440         struct ui_qnode *node = ui_current();
 441         vg_uictx.cursor[0] = node->rect[0] + node->rect[2] - vg_uictx.cursor[2];
 442 }
 443
 444 VG_STATIC void ui_align_top(void)
 445 {
 446         vg_uictx.cursor[1] = ui_current()->rect[1];
 447 }
 448
 449 VG_STATIC void ui_align_left(void)
 450 {
 451         vg_uictx.cursor[0] = ui_current()->rect[0];
 452 }
 453
 454 VG_STATIC void ui_clamp_rect( ui_rect parent, ui_rect dest )
 455 {
 456         dest[0] = vg_min( parent[0] + parent[2] - dest[2], dest[0] );
 457         dest[1] = vg_min( parent[1] + parent[3] - dest[3], dest[1] );
 458         dest[0] = vg_max( parent[0], dest[0] );
 459         dest[1] = vg_max( parent[1], dest[1] );
 460 }
 461
 462 VG_STATIC void ui_capture_mouse( u32 id )
 463 {
 464         struct ui_qnode *node = &vg_uictx.stack[ vg_uictx.stack_count-1 ];
 465         node->capture_id = id;
 466
 467         if( !vg_uictx.capture_lock && node->mouse_over )
 468         {
 469                 vg_uictx.capture_mouse_id = id;
 470         }
 471 }
 472
 473 static int ui_want_mouse(void)
 474 {
 475         return vg_uictx.capture_mouse_id == 0? 0: 1;
 476 }
 477
 478 VG_STATIC void ui_set_clip( ui_rect clip )
 479 {
 480         vg_uictx.clipping[0] = clip[0];
 481         vg_uictx.clipping[1] = clip[1];
 482         vg_uictx.clipping[2] = clip[0] + clip[2];
 483         vg_uictx.clipping[3] = clip[1] + clip[3];
 484 }
 485
 486 VG_STATIC void ui_release_clip(void)
 487 {
 488         vg_uictx.clipping[0] = -32000;
 489         vg_uictx.clipping[1] = -32000;
 490         vg_uictx.clipping[2] =  32000;
 491         vg_uictx.clipping[3] =  32000;
 492 }
 493
 494 static struct ui_vert *ui_fill_rect_uv( ui_rect rect, u32 colour, ui_px uv[4] )
 495 {
 496    struct ui_vert *vertices = &vg_uictx.vertex_buffer[ vg_uictx.num_verts ];
 497         u16            *indices  = &vg_uictx.indice_buffer[ vg_uictx.num_indices ];
 498
 499         vertices[0].co[0] = rect[0];
 500         vertices[0].co[1] = rect[1];
 501         vertices[0].uv[0] = uv[0];
 502         vertices[0].uv[1] = uv[1];
 503         vertices[0].colour = colour;
 504         vertices[1].co[0] = rect[0]+rect[2];
 505         vertices[1].co[1] = rect[1];
 506         vertices[1].uv[0] = uv[2];
 507         vertices[1].uv[1] = uv[1];
 508         vertices[1].colour = colour;
 509         vertices[2].co[0] = rect[0]+rect[2];
 510         vertices[2].co[1] = rect[1]+rect[3];
 511         vertices[2].uv[0] = uv[2];
 512         vertices[2].uv[1] = uv[3];
 513         vertices[2].colour = colour;
 514         vertices[3].co[0] = rect[0];
 515         vertices[3].co[1] = rect[1]+rect[3];
 516         vertices[3].uv[0] = uv[0];
 517         vertices[3].uv[1] = uv[3];
 518         vertices[3].colour = colour;
 519         u16 ind_start = vg_uictx.num_verts;
 520
 521         ui_rect_copy( vg_uictx.clipping, vertices[0].clip );
 522         ui_rect_copy( vg_uictx.clipping, vertices[1].clip );
 523         ui_rect_copy( vg_uictx.clipping, vertices[2].clip );
 524         ui_rect_copy( vg_uictx.clipping, vertices[3].clip );
 525
 526         indices[0] = ind_start+0;
 527         indices[1] = ind_start+2;
 528         indices[2] = ind_start+1;
 529
 530         indices[3] = ind_start+0;
 531         indices[4] = ind_start+3;
 532         indices[5] = ind_start+2;
 533
 534         vg_uictx.num_indices += 6;
 535         vg_uictx.num_verts += 4;
 536
 537         return vertices;
 538 }
 539
 540 static struct ui_vert *ui_fill_rect( ui_rect rect, u32 colour )
 541 {
 542         return ui_fill_rect_uv( rect, colour, (ui_px[4]){ 4,4, 4,4 } );
 543 }
 544
 545 static ui_px ui_text_line_offset( const char *str, ui_px scale,
 546       enum ui_text_align align )
 547 {
 548    if( align == k_text_align_left )
 549       return 0;
 550
 551    int length = 0;
 552    const char *_c = str;
 553    char c;
 554
 555    while( (c = *(_c ++)) )
 556       if( c >= 32 && c <= 126 )
 557          length ++;
 558       else if( c == '\n' )
 559          break;
 560
 561    if( align == k_text_align_right )
 562       return -length * scale*8;
 563    else
 564       return (-length * scale*8) / 2;
 565 }
 566
 567 VG_STATIC void ui_text( ui_px pos[2],
 568       const char *str, ui_px scale, enum ui_text_align align )
 569 {
 570         ui_rect text_cursor;
 571         u32 current_colour = 0x00ffffff;
 572
 573    const char *_c = str;
 574         u8 c;
 575
 576         text_cursor[0] = pos[0] + ui_text_line_offset( str, scale, align );
 577         text_cursor[1] = pos[1];
 578         text_cursor[2] = 8*scale;
 579         text_cursor[3] = 14*scale;
 580
 581         while( (c = *(_c ++)) )
 582         {
 583                 if( c == '\n' )
 584                 {
 585                         text_cursor[1] += 14*scale;
 586                         text_cursor[0] = pos[0] + ui_text_line_offset( _c, scale, align );
 587                         continue;
 588                 }
 589                 else if( c >= 33 )
 590                 {
 591                         u8 glyph_base[2];
 592                         u8 glyph_index = c;
 593                         glyph_base[0] = glyph_index & 0xf;
 594                         glyph_base[1] = (glyph_index-glyph_base[0])>>4;
 595
 596                         glyph_base[0] *= 8;
 597                         glyph_base[1] *= 8;
 598
 599                         ui_fill_rect_uv( text_cursor, current_colour, (ui_px[4])
 600             {
 601                glyph_base[0]+2,
 602                glyph_base[1]+1,
 603                glyph_base[0]+6,
 604                glyph_base[1]+8
 605             });
 606                 }
 607                 else if( c == '\x1B' )
 608                 {
 609                         _c ++;
 610                         u16 colour_id = 0;
 611                         for( int i = 0; i < 3; i ++ )
 612                         {
 613                                 if( _c[i] )
 614                                 {
 615                                         if( _c[i] == 'm' )
 616                                         {
 617                                                 _c = _c + i + 1;
 618
 619                                                 switch( colour_id )
 620                                                 {
 621                                                         case '0': current_colour = 0x00ffffff; break;
 622                                                         case '3'|'1'<<8: current_colour = 0x00201fee; break;
 623                                                         case '3'|'2'<<8: current_colour = 0x0037e420; break;
 624                                                         case '3'|'3'<<8: current_colour = 0x000ed8e2; break;
 625                                                         case '3'|'4'<<8: current_colour = 0x00f15010; break;
 626                                                         case '3'|'5'<<8: current_colour = 0x00ee20ee; break;
 627                                                         case '3'|'6'<<8: current_colour = 0x00eeee20; break;
 628                                                         case '3'|'7'<<8: current_colour = 0x00ffffff; break;
 629                                                 }
 630
 631                                                 break;
 632                                         }
 633
 634                                         colour_id |= _c[i] << (i*8);
 635                                 }
 636                                 else
 637                                 {
 638                                         _c = _c +i;
 639                                         break;
 640                                 }
 641                         }
 642
 643          continue;
 644                 }
 645       else if( c == '\t' )
 646       {
 647          text_cursor[0] += UI_GLYPH_SPACING_X*scale*4;
 648          continue;
 649       }
 650
 651         text_cursor[0] += UI_GLYPH_SPACING_X*scale;
 652         }
 653 }
 654
 655 /*
 656  * API Control
 657  */
 658 VG_STATIC void ui_begin( ui_px res_x, ui_px res_y )
 659 {
 660         vg_uictx.cursor[0] = 0;
 661         vg_uictx.cursor[1] = 0;
 662         vg_uictx.cursor[2] = res_x;
 663         vg_uictx.cursor[3] = res_y;
 664
 665         ui_rect_copy( vg_uictx.cursor, vg_uictx.stack[0].rect );
 666         vg_uictx.stack[0].mouse_over = 1;
 667
 668         vg_uictx.stack_count = 1;
 669
 670         vg_uictx.num_verts = 0;
 671         vg_uictx.num_indices = 0;
 672
 673         ui_release_clip();
 674
 675         if( vg_uictx.click_state == 0 )
 676                 vg_uictx.capture_mouse_id = 0;
 677
 678         vg_uictx.image_count = 0;
 679 }
 680
 681 VG_STATIC void ui_resolve(void)
 682 {
 683         if( vg_uictx.stack_count-1 )
 684    {
 685       vg_error( "[UI] Mismatched node create/drestroy!" );
 686       return;
 687    }
 688
 689         if( vg_uictx.click_state == 3 || vg_uictx.click_state == 0 )
 690         {
 691                 vg_uictx.capture_lock = 0;
 692         }
 693 }
 694
 695 VG_STATIC void ui_set_mouse( int x, int y, int click_state )
 696 {
 697         vg_uictx.mouse[0] = x;
 698         vg_uictx.mouse[1] = y;
 699
 700         vg_uictx.click_state = click_state;
 701 }
 702
 703 /*
 704  * High level controls
 705  */
 706 struct ui_window
 707 {
 708         const char *title;
 709         ui_rect transform;
 710
 711         int     drag;
 712         ui_px drag_offset[2];
 713 };
 714
 715 enum button_state
 716 {
 717         k_button_released = 0,
 718         k_button_start_click,
 719         k_button_click,
 720         k_button_hold
 721 };
 722
 723 static int ui_button(void)
 724 {
 725    u32 uid = vg_uictx.control_id ++;
 726
 727         ui_new_node();
 728         {
 729                 ui_capture_mouse( uid );
 730
 731                 if( ui_hasmouse() )
 732                 {
 733                         ui_fill_rect( vg_uictx.cursor, vg_uictx.colours->hover );
 734
 735                         if( vg_uictx.click_state == 1 )
 736                         {
 737                                 vg_uictx.capture_lock = 1;
 738                                 return k_button_start_click;
 739                         }
 740                         else if( vg_uictx.capture_lock && vg_uictx.click_state == 3 )
 741                                 return k_button_click;
 742                         else if( vg_uictx.capture_lock && vg_uictx.click_state == 2 )
 743                                 return k_button_hold;
 744
 745          return k_button_click;
 746                 }
 747                 else
 748                         ui_fill_rect( vg_uictx.cursor, vg_uictx.colours->main );
 749         }
 750
 751         return k_button_released;
 752 }
 753
 754 static int ui_window( struct ui_window *window, u32 control_group )
 755 {
 756         if( window->drag )
 757         {
 758                 window->transform[0] = vg_uictx.mouse[0]+window->drag_offset[0];
 759                 window->transform[1] = vg_uictx.mouse[1]+window->drag_offset[1];
 760
 761                 ui_clamp_rect( vg_uictx.stack[0].rect, window->transform );
 762
 763                 if( vg_uictx.click_state == 0 || vg_uictx.click_state == 3 )
 764                 {
 765                         window->drag = 0;
 766                 }
 767         }
 768
 769         ui_rect_copy( window->transform, vg_uictx.cursor );
 770
 771         ui_new_node();
 772         {
 773                 ui_capture_mouse( vg_uictx.control_id ++ );
 774
 775                 /* Drag bar */
 776                 vg_uictx.cursor[3] = 25;
 777                 ui_new_node();
 778                 {
 779                         ui_capture_mouse( vg_uictx.control_id ++ );
 780
 781                         struct ui_vert *drag_bar = ui_fill_rect( vg_uictx.cursor, 0xff555555 );
 782
 783                         /* title.. */
 784                         vg_uictx.cursor[0] += 2;
 785                         vg_uictx.cursor[1] += 2;
 786                         ui_text( vg_uictx.cursor, window->title, 2, 0 );
 787
 788                         /* Close button */
 789                         vg_uictx.cursor[3] = 25;
 790                         vg_uictx.cursor[2] = 25;
 791                         ui_align_right();
 792                         ui_align_top();
 793                         ui_rect_pad( vg_uictx.cursor, 4 );
 794
 795                         if( ui_button() )
 796                         {
 797                                 vg_info( "Click clacked\n" );
 798                         }
 799                         vg_uictx.cursor[0] += 2;
 800                         ui_text( vg_uictx.cursor, "x", 2, 0 );
 801                         ui_end();
 802
 803                         if( ui_hasmouse() )
 804                         {
 805                                 drag_bar[0].colour = 0xff777777;
 806                                 drag_bar[1].colour = 0xff777777;
 807                                 drag_bar[2].colour = 0xff777777;
 808                                 drag_bar[3].colour = 0xff777777;
 809
 810                                 /* start drag */
 811                                 if( vg_uictx.click_state == 1 )
 812                                 {
 813                                         window->drag = 1;
 814                                         window->drag_offset[0] = window->transform[0]-vg_uictx.mouse[0];
 815                                         window->drag_offset[1] = window->transform[1]-vg_uictx.mouse[1];
 816                                 }
 817                         }
 818                 }
 819                 ui_end_down();
 820         }
 821
 822         return 1;
 823 }
 824
 825 VG_STATIC void ui_push_image( ui_rect rc, GLuint image )
 826 {
 827         struct ui_image *img = &vg_uictx.images[ vg_uictx.image_count ++ ];
 828         ui_rect_copy( rc, img->rc );
 829         img->image = image;
 830 }
 831
 832 struct ui_slider
 833 {
 834    float *data;
 835    float min, max;
 836 };
 837
 838 struct ui_slider_vector
 839 {
 840    float *data, min, max;
 841    struct ui_slider sub[4];
 842    u32 len;
 843 };
 844
 845 struct ui_checkbox
 846 {
 847    int *data;
 848 };
 849
 850 VG_STATIC void ui_slider( struct ui_slider *slider )
 851 {
 852    ui_new_node();
 853
 854    ui_px slider_start = vg_uictx.cursor[0];
 855
 856    float const ftotal = vg_uictx.cursor[2],
 857                fwidth = ftotal*0.25f,
 858                fmove  = ftotal - fwidth,
 859                fstart = fwidth*0.5f,
 860                frange = slider->max-slider->min,
 861                fpos   = (*slider->data - slider->min) / frange;
 862
 863    ui_fill_rect( vg_uictx.cursor, 0xff111111 );
 864    vg_uictx.cursor[2] = fwidth;
 865    vg_uictx.cursor[0] = slider_start + fpos * fmove;
 866
 867    u32 uid = vg_uictx.control_id ++;
 868    int status = ui_button();
 869    if( vg_uictx.capture_lock && (vg_uictx.capture_mouse_id == uid))
 870    {
 871       float ui_new = vg_uictx.mouse[0],
 872             local  = ui_new - (slider_start + fstart),
 873             zo     = vg_clampf(local / fmove,0.0f,1.0f);
 874
 875       *slider->data = vg_lerpf( slider->min, slider->max, zo );
 876    }
 877
 878    vg_uictx.cursor[0] += 4;
 879    vg_uictx.cursor[1] += 4;
 880
 881    char buf[12];
 882    snprintf( buf, 12, "%.2f", *slider->data );
 883    ui_text( vg_uictx.cursor, buf, 1, 0 );
 884    ui_end_down();
 885    ui_end_down();
 886 }
 887
 888 VG_STATIC void ui_slider_vector( struct ui_slider_vector *slider )
 889 {
 890    for( int i=0; i<slider->len; i++ )
 891    {
 892       slider->sub[i].data = &slider->data[i];
 893       slider->sub[i].min = slider->min;
 894       slider->sub[i].max = slider->max;
 895       ui_slider( &slider->sub[i] );
 896    }
 897 }
 898
 899 VG_STATIC void ui_checkbox( struct ui_checkbox *cb )
 900 {
 901    if( ui_button() == k_button_click )
 902       *cb->data ^= 0x1;
 903
 904    ui_new_node();
 905    ui_rect_pad( vg_uictx.cursor, 4 );
 906    if( *cb->data )
 907       ui_fill_rect( vg_uictx.cursor, 0xff00e052 );
 908    else
 909       ui_fill_rect( vg_uictx.cursor, 0xff0052e0 );
 910
 911    ui_end();
 912    ui_end_down();
 913 }
 914
 915 #endif /* VG_UI_H */