lazarus-ccr/components/nvidia-widgets/examples/example.pp

program example;

{$mode objfpc}
{$H+}

uses
  Classes, SysUtils,
  GLut, GL, GLu,
  nvWidgets, nvGlutWidgets;

type
  UIOption = (
    OPTION_DIFF,
    OPTION_DXT5_YCOCG,
    OPTION_COMPRESS,
    OPTION_ANIMATE,
    OPTION_THUMBNAIL,
    OPTION_COUNT);

var
  options: array [UIOption] of boolean;
  ui: GlutUIContext;
  win_w: integer = 512;
  win_h: integer = 512;
  errorScale: double = 4;
  compressionRate: double = 1;
  texture: GLuint = 0;

  procedure closeapp;
  begin
    FreeAndNil(ui);
    halt(0);
  end;

  procedure idle; cdecl;
  begin
    glutPostRedisplay;
  end;

  procedure key(k: byte; x: integer; y: integer); cdecl;
  begin
    ui.keyboard(k, x, y);

    case k of
      27, Ord('q'):
        closeapp;
    end;
  end;

  procedure special(key: integer; x: integer; y: integer); cdecl;
  begin
    ui.specialKeyboard(key, x, y);
  end;

  procedure resize(w: integer; h: integer); cdecl;
  begin
    ui.reshape(w, h);
    glViewport(0, 0, w, h);

    win_w := w;
    win_h := h;
  end;

  procedure mouse(button: integer; state: integer; x: integer; y: integer); cdecl;
  begin
    ui.mouse(button, state, x, y);
  end;

  procedure motion(x: integer; y: integer); cdecl;
  begin
    ui.mouseMotion(x, y);
  end;

  procedure doUI;
  const
    formatLabel: array [0..1] of string = ('YCoCg-DXT5', 'DXT1');
  var
    none: Rect;
    formatIdx: integer;
    Text: string;
    textureRect: Rect;
  begin
    none.Rect(0, 0);

    ui._begin;

    ui.beginGroup(GroupFlags_GrowDownFromLeft);

    ui.doCheckButton(none, 'Enable compression', options[OPTION_COMPRESS]);

    if options[OPTION_COMPRESS] then
    begin
      ui.beginGroup(GroupFlags_GrowLeftFromTop or GroupFlags_LayoutNoMargin);
      ui.doCheckButton(none, 'Show difference', options[OPTION_DIFF]);

      ui.beginPanel(none, 'panel', true);
      ui.doCheckButton(none, 'Show difference', options[OPTION_DIFF]);
      ui.endPanel;

      if options[OPTION_DIFF] then
        ui.doHorizontalSlider(none, 1, 16, errorScale);

      ui.endGroup;

      ui.beginGroup(GroupFlags_GrowLeftFromTop);
      ui.doLabel(none, 'Format');

      if options[OPTION_DXT5_YCOCG] then
        formatIdx := 0
      else
        formatIdx := 1;

      ui.doComboBox(none, 2, formatLabel, formatIdx);
      options[OPTION_DXT5_YCOCG] := formatIdx = 0;
      ui.endGroup;
    end;

    ui.doCheckButton(none, 'Display dummy texture', options[OPTION_THUMBNAIL]);

    if options[OPTION_THUMBNAIL] then
    begin
      textureRect.Rect(0, 0, 100, 100);
      ui.doTextureView(textureRect, texture, textureRect);
    end;
    ui.endGroup;

    if options[OPTION_COMPRESS] then
    begin
      ui.beginGroup(GroupFlags_GrowDownFromRight);

      if ui.doButton(none, 'Benchmark') then
      begin
        // doBenchmark = true;
      end;

      if compressionRate <> 0 then
      begin
        Text := Format('%.2d Mpixels/sec', [100]);
        ui.doLabel(none, Text);
      end;

      ui.endGroup;
    end;

    // Pass non-ui mouse events to the manipulator
    //updateManipulator(ui, manipulator);

    ui._end;
  end;

  procedure display; cdecl;
  begin
    glClear(GL_COLOR_BUFFER_BIT or GL_DEPTH_BUFFER_BIT);
    glMatrixMode(GL_MODELVIEW);

    glLoadIdentity;
    doUI;
    glutSwapBuffers;
  end;

var
  texture_data: array [0..3] of cardinal = ($FFFF0000, $FF0000FF, $FF00FF00, $FF00FF00);

begin
  glutInit(@argc, argv);
  glutInitWindowSize(win_w, win_h);
  glutInitDisplayMode(GLUT_DOUBLE or GLUT_DEPTH or GLUT_RGB);
  glutCreateWindow('UI example');

  ui := GlutUIContext.Create;

  if not ui.init(win_w, win_h) then
  begin
    writeln('UI initialization failed');
    closeapp;
  end;

  glutReportErrors;

  glGenTextures(1, @texture);
  glBindTexture(GL_TEXTURE_2D, texture);
  gluBuild2DMipmaps(GL_TEXTURE_2D, GL_RGBA, 2, 2, GL_RGBA, GL_UNSIGNED_BYTE, @texture_data);
  glEnable(GL_DEPTH_TEST);
  glClearColor(0, 0, 0, 1);
  glutDisplayFunc(@display);

  glutMouseFunc(@mouse);
  glutMotionFunc(@motion);
  glutPassiveMotionFunc(@motion);
  glutIdleFunc(@idle);
  glutKeyboardFunc(@key);
  glutSpecialFunc(@special);
  glutReshapeFunc(@resize);
  glutMainLoop;
end.