vg_loader.h

   1 /*
   2  * Copyright 2021-2022 (C) Mount0 Software, Harry Godden - All Rights Reserved
   3  * -----------------------------------------------------------------------------
   4  *
   5  * Splash / load screen
   6  *
   7  * -----------------------------------------------------------------------------
   8  */
   9
  10 #ifndef VG_LOADER_H
  11 #define VG_LOADER_H
  12
  13 #include "common.h"
  14
  15 VG_STATIC void vg_loader_start( void(*pfn)(void) );
  16 VG_STATIC void vg_loader_step( void( *fn_load )(void), void( *fn_free )(void) );
  17
  18 static struct vg_shader _shader_loader =
  19 {
  20    .name = "[vg] loader",
  21    .link = NULL,
  22    .vs =
  23    {
  24       .orig_file = NULL,
  25       .static_src = ""
  26       "layout (location=0) in vec2 a_co;"
  27       "out vec2 aUv;"
  28       "void main()"
  29       "{"
  30          "gl_Position = vec4(a_co*2.0-1.0,0.0,1.0);"
  31          "aUv = a_co;"
  32       "}"
  33    },
  34    .fs =
  35    {
  36       .orig_file = NULL,
  37       .static_src =
  38
  39       "out vec4 FragColor;"
  40       "uniform float uTime;"
  41       "in vec2 aUv;"
  42
  43       "void main()"
  44       "{"
  45          "float dither=fract(dot(vec2(171.0,231.0),gl_FragCoord.xy)/71.0)-0.5;"
  46          "float grad = 1.0-(aUv.y*0.5+0.5)*0.5;"
  47          "float fmt1 = step( 0.5, grad+dither );"
  48
  49          "vec3 col = 0.5+0.5*sin( uTime + aUv.xyx + vec3(0.0,2.0,4.0) );"
  50
  51          "FragColor = vec4(vec3(0.5,0.5,0.5)*grad*fmt1,1.0);"
  52       "}"
  53    }
  54 };
  55
  56 static struct vg_loader
  57 {
  58    /* Shutdown steps */
  59    struct loader_free_step
  60    {
  61       void (*fn_free)(void);
  62    }
  63    step_buffer[16];
  64    u32 step_count, step_action;
  65
  66    GLuint vao, vbo;
  67 }
  68 vg_loader;
  69
  70 VG_STATIC void _vg_loader_init(void)
  71 {
  72    float quad[] = { 0.0f, 0.0f, 1.0f, 1.0f, 0.0f, 1.0f,
  73                     0.0f, 0.0f, 1.0f, 0.0f, 1.0f, 1.0f };
  74
  75    glGenVertexArrays( 1, &vg_loader.vao );
  76    glGenBuffers( 1, &vg_loader.vbo );
  77    glBindVertexArray( vg_loader.vao );
  78    glBindBuffer( GL_ARRAY_BUFFER, vg_loader.vbo );
  79    glBufferData( GL_ARRAY_BUFFER, sizeof(quad), quad, GL_STATIC_DRAW );
  80    glBindVertexArray( vg_loader.vao );
  81    glVertexAttribPointer( 0, 2, GL_FLOAT, GL_FALSE, sizeof(float)*2, (void*)0 );
  82    glEnableVertexAttribArray( 0 );
  83
  84    VG_CHECK_GL_ERR();
  85
  86    if( !vg_shader_compile( &_shader_loader ) )
  87       vg_fatal_exit_loop( "failed to compile shader" );
  88 }
  89
  90 VG_STATIC void _vg_loader_free(void)
  91 {
  92    vg_info( "vg_loader_free\n" );
  93    glDeleteVertexArrays( 1, &vg_loader.vao );
  94    glDeleteBuffers( 1, &vg_loader.vbo );
  95
  96    for( int i=0; i<vg_loader.step_count; i++ )
  97    {
  98       struct loader_free_step *step =
  99          &vg_loader.step_buffer[vg_loader.step_count -1 -i];
 100
 101       vg_info( " -> %p\n", step->fn_free );
 102       step->fn_free();
 103    }
 104
 105    vg_info( "done\n" );
 106 }
 107
 108 VG_STATIC void _vg_render_log(void)
 109 {
 110    ui_begin( vg.window_x, vg.window_y );
 111    SDL_AtomicLock( &log_print_sl );
 112
 113    int const fh = 14;
 114    int lines_screen_max = ((vg.window_y/fh)-2),
 115        lines_max_draw = VG_MIN( lines_screen_max, vg_list_size(vg_log.buffer) ),
 116        lines_to_draw  = VG_MIN( lines_max_draw, vg_log.buffer_line_count );
 117
 118         int ptr = vg_log.buffer_line_current;
 119
 120         vg_uictx.cursor[0] = 0;
 121         vg_uictx.cursor[1] = lines_to_draw*fh;
 122    vg_uictx.cursor[3] = fh;
 123         ui_fill_x();
 124
 125    for( int i=0; i<lines_to_draw; i ++ )
 126    {
 127       ptr --;
 128
 129       if( ptr < 0 )
 130          ptr = vg_list_size( vg_log.buffer )-1;
 131
 132       ui_text( vg_uictx.cursor, vg_log.buffer[ptr], 1, 0 );
 133       vg_uictx.cursor[1] -= fh;
 134    }
 135
 136    SDL_AtomicUnlock( &log_print_sl );
 137
 138    ui_resolve();
 139    ui_draw( NULL );
 140 }
 141
 142 VG_STATIC void _vg_loader_render(void)
 143 {
 144    glViewport( 0,0, vg.window_x, vg.window_y );
 145    glBindFramebuffer( GL_FRAMEBUFFER, 0 );
 146    glClearColor( 0.0f, 0.0f, 0.0f, 1.0f );
 147    glClear( GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT );
 148
 149    glUseProgram( _shader_loader.id );
 150         glUniform1f( glGetUniformLocation( _shader_loader.id, "uTime" ), vg.time );
 151
 152    glBindVertexArray( vg_loader.vao );
 153    glDrawArrays( GL_TRIANGLES, 0, 6 );
 154
 155    _vg_render_log();
 156 }
 157
 158
 159 VG_STATIC void vg_load_full(void);
 160
 161 VG_STATIC int _vg_loader_thread(void *pfn)
 162 {
 163    SDL_AtomicLock( &vg.sl_context );
 164    vg.thread_id_loader = SDL_GetThreadID(NULL);
 165    VG_SYNC_LOG( "[%d] Loader thread begins\n" );
 166    SDL_AtomicUnlock( &vg.sl_context );
 167
 168    /* Run client loader */
 169    void (*call_func)(void) = pfn;
 170    call_func();
 171
 172    SDL_SemPost( vg.sem_loader );
 173    vg.thread_id_loader = 0;
 174
 175    vg_acquire_thread_sync();
 176    vg.is_loaded = 1;
 177    vg_release_thread_sync();
 178
 179    return 0;
 180 }
 181
 182 VG_STATIC void vg_loader_start( void(*pfn)(void) )
 183 {
 184    vg.is_loaded = 0;
 185    SDL_SemWait( vg.sem_loader );
 186    SDL_CreateThread( _vg_loader_thread, "Loader thread", pfn );
 187 }
 188
 189 /*
 190  * Schedule something to be ran now, freed later. Checks in with engine status
 191  */
 192 VG_STATIC void vg_loader_step( void( *fn_load )(void), void( *fn_free )(void) )
 193 {
 194    if( fn_load )
 195       fn_load();
 196
 197    if( fn_free )
 198    {
 199       struct loader_free_step step;
 200       step.fn_free = fn_free;
 201
 202       if( vg_loader.step_count == vg_list_size(vg_loader.step_buffer) )
 203          vg_fatal_exit_loop( "Too many free steps" );
 204
 205       vg_loader.step_buffer[ vg_loader.step_count ++ ] = step;
 206    }
 207
 208    _vg_ensure_engine_running();
 209 }
 210
 211 #endif /* VG_LOADER_H */