src/vg/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 static struct vg_shader _shader_loader =
  16 {
  17    .name = "[vg] loader",
  18    .link = NULL,
  19    .vs =
  20    {
  21       .orig_file = NULL,
  22       .static_src = ""
  23       "layout (location=0) in vec2 a_co;"
  24       "out vec2 aUv;"
  25       "void main()"
  26       "{"
  27          "gl_Position = vec4(a_co*2.0-1.0,0.0,1.0);"
  28          "aUv = a_co;"
  29       "}"
  30    },
  31    .fs =
  32    {
  33       .orig_file = NULL,
  34       .static_src =
  35
  36       "out vec4 FragColor;"
  37       "uniform float uTime;"
  38       "in vec2 aUv;"
  39
  40       "void main()"
  41       "{"
  42          "float dither=fract(dot(vec2(171.0,231.0),gl_FragCoord.xy)/71.0)-0.5;"
  43          "float grad = 1.0-(aUv.y*0.5+0.5);"
  44          "float fmt1 = step( 0.5, grad+dither );"
  45
  46          "vec3 col = 0.5+0.5*sin( uTime + aUv.xyx + vec3(0.0,2.0,4.0) );"
  47
  48          "FragColor = vec4(col*grad*fmt1,1.0);"
  49       "}"
  50    }
  51 };
  52
  53 static struct vg_loader
  54 {
  55    /* Shutdown steps */
  56    struct loader_free_step
  57    {
  58       void (*fn_free)(void *);
  59       void *data;
  60    }
  61    *step_buffer;
  62    u32 step_count, step_cap, step_action;
  63
  64    GLuint vao, vbo;
  65 }
  66 vg_loader;
  67
  68 static int vg_loader_init(void)
  69 {
  70    float quad[] = { 0.0f, 0.0f, 1.0f, 1.0f, 0.0f, 1.0f,
  71                     0.0f, 0.0f, 1.0f, 0.0f, 1.0f, 1.0f };
  72
  73    glGenVertexArrays( 1, &vg_loader.vao );
  74    glGenBuffers( 1, &vg_loader.vbo );
  75    glBindVertexArray( vg_loader.vao );
  76    glBindBuffer( GL_ARRAY_BUFFER, vg_loader.vbo );
  77    glBufferData( GL_ARRAY_BUFFER, sizeof(quad), quad, GL_STATIC_DRAW );
  78    glBindVertexArray( vg_loader.vao );
  79    glVertexAttribPointer( 0, 2, GL_FLOAT, GL_FALSE,
  80          sizeof(float)*2, (void*)0 );
  81    glEnableVertexAttribArray( 0 );
  82
  83    VG_CHECK_GL_ERR();
  84
  85    if( !vg_shader_compile( &_shader_loader ) )
  86    {
  87       glDeleteVertexArrays( 1, &vg_loader.vao );
  88       glDeleteBuffers( 1, &vg_loader.vbo );
  89       return 0;
  90    }
  91
  92    return 1;
  93 }
  94
  95 static void vg_loader_free(void)
  96 {
  97    vg_info( "vg_loader_free\n" );
  98    glDeleteVertexArrays( 1, &vg_loader.vao );
  99    glDeleteBuffers( 1, &vg_loader.vbo );
 100
 101    for( int i=0; i<vg_loader.step_count; i++ )
 102    {
 103       struct loader_free_step *step =
 104          &vg_loader.step_buffer[vg_loader.step_count -1 -i];
 105
 106       vg_info( " -> %p\n", step->fn_free );
 107       step->fn_free( step->data );
 108    }
 109
 110    vg_free( vg_loader.step_buffer );
 111    vg_info( "done\n" );
 112 }
 113
 114 static float hue_to_rgb( float p, float q, float t )
 115 {
 116    if(t < 0.0f) t += 1.0f;
 117    if(t > 1.0f) t -= 1.0f;
 118    if(t < 1.0f/6.0f) return p + (q - p) * 6.0f * t;
 119    if(t < 1.0f/2.0f) return q;
 120    if(t < 2.0f/3.0f) return p + (q - p) * (2.0f/3.0f - t) * 6.0f;
 121    return p;
 122 }
 123
 124 static void vg_render_log(void)
 125 {
 126    ui_begin( &ui_global_ctx, vg_window_x, vg_window_y );
 127
 128
 129    int const fh = 14;
 130    int lines_screen_max = ((vg_window_y/fh)-2),
 131        lines_max_draw = VG_MIN( lines_screen_max, vg_list_size(vg_log.buffer) ),
 132        lines_to_draw  = VG_MIN( lines_max_draw, vg_log.buffer_line_count );
 133
 134         int ptr = vg_log.buffer_line_current;
 135
 136         ui_global_ctx.cursor[0] = 0;
 137         ui_global_ctx.cursor[1] = lines_to_draw*fh;
 138    ui_global_ctx.cursor[3] = fh;
 139         ui_fill_x( &ui_global_ctx );
 140
 141    for( int i=0; i<lines_to_draw; i ++ )
 142    {
 143       ptr --;
 144
 145       if( ptr < 0 )
 146          ptr = vg_list_size( vg_log.buffer )-1;
 147
 148       ui_text( &ui_global_ctx, ui_global_ctx.cursor,
 149             vg_log.buffer[ptr], vg_console.scale, 0 );
 150
 151       ui_global_ctx.cursor[1] -= fh*vg_console.scale;
 152    }
 153
 154    ui_resolve( &ui_global_ctx );
 155    ui_draw( &ui_global_ctx, NULL );
 156 }
 157
 158 static void vg_loader_render(void)
 159 {
 160    glViewport( 0,0, vg_window_x, vg_window_y );
 161    glBindFramebuffer( GL_FRAMEBUFFER, 0 );
 162    glClearColor( 0.0f, 0.0f, 0.0f, 1.0f );
 163    glClear( GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT );
 164
 165    glUseProgram( _shader_loader.id );
 166         glUniform1f( glGetUniformLocation( _shader_loader.id, "uTime" ), vg_time );
 167
 168    glBindVertexArray( vg_loader.vao );
 169    glDrawArrays( GL_TRIANGLES, 0, 6 );
 170
 171    vg_render_log();
 172 }
 173
 174
 175 static void vg_load_full(void);
 176
 177 static void vg_loader_thread(void * nothing)
 178 {
 179    vg_thread_info.gl_context_level = 0;
 180    vg_thread_info.purpose = k_thread_purpose_loader;
 181    vg_set_thread_name( "[vg] Loader" );
 182
 183    /* Run client loader */
 184    vg_load_full();
 185    vg_semaphore_post( &vg.sem_loader );
 186 }
 187
 188 static void vg_loader_start(void)
 189 {
 190    vg_semaphore_wait( &vg.sem_loader );
 191    vg_thread_run( vg_loader_thread, NULL );
 192 }
 193
 194 static void vg_free_libc_malloced( void *data )
 195 {
 196    vg_free( data );
 197 }
 198
 199 static void vg_loader_push_free_step( struct loader_free_step step )
 200 {
 201    vg_loader.step_buffer =
 202       buffer_reserve( vg_loader.step_buffer, vg_loader.step_count,
 203                               &vg_loader.step_cap, 1,
 204                               sizeof( struct loader_free_step ) );
 205
 206    vg_loader.step_buffer[ vg_loader.step_count ++ ] = step;
 207 }
 208
 209 /*
 210  * Schedule something to be ran now, freed later
 211  */
 212 static void vg_loader_highwater( void( *fn_load )(void),
 213                                  void( *fn_free )(void *), void *data )
 214 {
 215    if( fn_load )
 216       fn_load();
 217
 218    if( fn_free )
 219    {
 220       struct loader_free_step step;
 221       step.data = data;
 222       step.fn_free = fn_free;
 223
 224       vg_loader_push_free_step( step );
 225    }
 226    else
 227    {
 228       if( data )
 229       {
 230          struct loader_free_step step;
 231          step.data = data;
 232          step.fn_free = vg_free_libc_malloced;
 233
 234          vg_loader_push_free_step( step );
 235       }
 236    }
 237
 238    vg_ensure_engine_running();
 239 }
 240
 241 #endif /* VG_LOADER_H */