fpc/packages/libndsfpc/examples/graphics/3D/nehe/lesson09/lesson09.pp

(****************************************
 *    NDS NeHe Lesson 09          *
 *    Author: dovoto
 *    DS does not appear to support 
    the features needed for this demo
 ****************************************)

program Lesson09;
{$L build/star.pcx.o}

{$mode objfpc}

uses
  ctypes, nds9;

type
  TStars = record       // Create A Structure For Star
    r, g, b: cint;   // Stars Color
    dist: cfloat;       // Stars Distance From Center
    angle: cfloat;      // Stars Current Angle
  end;


{$include inc/star.pcx.inc}


var
  twinkle: boolean;   // Twinkling Stars
  tp: boolean;        // 'T' Key Pressed?

const 
  num = 50;   // Number Of Stars To Draw


var
  star: array [0..num-1] of TStars;   // Need To Keep Track Of 'num' Stars
  zoom: cfloat = -15.0; // Distance Away From Stars
  tilt: cfloat = 90.0;    // Tilt The View
  spin: cfloat;     // Spin Stars

  loop: integer;      // General Loop Variable
  texture: array [0..0] of integer;     // Storage For One textures



// Load PCX files And Convert To Textures
function LoadGLTextures(): boolean;                 // Load PCX files And Convert To Textures
var
  pcx: sImage;                //////////////(NEW) and different from nehe.
begin
  //load our texture
  loadPCX(pcuint8(Star_pcx), @pcx);
  
  image8to16(@pcx);

  glGenTextures(1, @texture[0]);
  glBindTexture(0, texture[0]);
  glTexImage2D(0, 0, GL_RGBA, TEXTURE_SIZE_128 , TEXTURE_SIZE_128, 0, TEXGEN_TEXCOORD, pcx.image.data8);

  imageDestroy(@pcx);

  result := true;
end;

function DrawGLScene(): boolean;                      // Here's Where We Do All The Drawing
var
  loop: integer;
begin
  glBindTexture(GL_TEXTURE_2D, texture[0]);     // Select Our Texture

  for loop := 0 to num - 1 do           // Loop Through All The Stars
  begin
    glLoadIdentity();               // Reset The View Before We Draw Each Star
    glTranslatef(0.0, 0.0, zoom);         // Zoom Into The Screen (Using The Value In 'zoom')
    glRotatef(tilt, 1.0, 0.0, 0.0);         // Tilt The View (Using The Value In 'tilt')
    glRotatef(star[loop].angle, 0.0, 1.0, 0.0);   // Rotate To The Current Stars Angle
    glTranslatef(star[loop].dist, 0.0, 0.0);    // Move Forward On The X Plane
    glRotatef(-star[loop].angle, 0.0, 1.0, 0.0);  // Cancel The Current Stars Angle
    glRotatef(-tilt, 1.0, 0.0, 0.0);        // Cancel The Screen Tilt
    
    if (twinkle) then
    begin
      glColor3b(star[(num-loop)-1].r,star[(num-loop)-1].g,star[(num-loop)-1].b);  ///different
      glBegin(GL_QUADS);
        glTexCoord2f(0.0, 0.0); glVertex3f(-1.0,-1.0, 0.0);
        glTexCoord2f(1.0, 0.0); glVertex3f( 1.0,-1.0, 0.0);
        glTexCoord2f(1.0, 1.0); glVertex3f( 1.0, 1.0, 0.0);
        glTexCoord2f(0.0, 1.0); glVertex3f(-1.0, 1.0, 0.0);
      glEnd();
    end;

    glRotatef(spin, 0.0, 0.0, 1.0);
    glColor3b(star[loop].r,star[loop].g,star[loop].b);                            //different
    glBegin(GL_QUADS);
      glTexCoord2f(0.0, 0.0); glVertex3f(-1.0,-1.0, 0.0);
      glTexCoord2f(1.0, 0.0); glVertex3f( 1.0,-1.0, 0.0);
      glTexCoord2f(1.0, 1.0); glVertex3f( 1.0, 1.0, 0.0);
      glTexCoord2f(0.0, 1.0); glVertex3f(-1.0, 1.0, 0.0);
    glEnd();

    spin := spin + 0.01;
    star[loop].angle := star[loop].angle + cfloat(loop) / num;
    star[loop].dist := star[loop].dist - 0.01;
    if (star[loop].dist < 0.0) then
    begin
      star[loop].dist := star[loop].dist + 5.0;
      star[loop].r := random(256);
      star[loop].g := random(256);
      star[loop].b := random(256);
    end;
  end;
  result := true;                             // Keep Going

end;

var
  pressed: integer;
begin
  Randomize;
  // Setup the Main screen for 3D 
  videoSetMode(MODE_0_3D);
  vramSetBankA(VRAM_A_TEXTURE);                        //NEW  must set up some memory for textures

  // initialize the geometry engine
  glInit();
  
  // enable antialiasing
  glEnable(GL_ANTIALIAS);
  
  // setup the rear plane
  glClearColor(0,0,0,31); // BG must be opaque for AA to work
  glClearPolyID(63); // BG must have a unique polygon ID for AA to work
  glClearDepth($7FFF);
  
  // enable textures
  glEnable(GL_TEXTURE_2D);
  
  // enable alpha blending
  glEnable(GL_BLEND);

  // Set our viewport to be the same size as the screen
  glViewport(0,0,255,191);
  
  LoadGLTextures();
  
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  gluPerspective(70, 256.0 / 192.0, 0.1, 100);
  glColor3f(1,1,1);
  
  //set up a directional ligth arguments are light number (0-3), light color, 
  //and an x,y,z vector that points in the direction of the light
  glLight(0, RGB15(31,31,31), 0, 0, floattov10(-1.0));
  
  //need to set up some material properties since DS does not have them set by default
  glMaterialf(GL_AMBIENT, RGB15(16,16,16));
  glMaterialf(GL_DIFFUSE, RGB15(16,16,16));
  glMaterialf(GL_SPECULAR, BIT(15) or RGB15(8,8,8));
  glMaterialf(GL_EMISSION, RGB15(16,16,16));
  
  //ds uses a table for shinyness..this generates a half-ass one
  glMaterialShinyness();
  
  glPolyFmt(POLY_ALPHA(15) or POLY_CULL_BACK or POLY_FORMAT_LIGHT0);

  glMatrixMode(GL_MODELVIEW);
  
  while true do
  begin
    DrawGLScene();
    
    // flush to screen  
    glFlush(0);
    
    // wait for the screen to refresh
    swiWaitForVBlank();
    scanKeys();
    pressed := keysDown();
    if (pressed and KEY_START) <> 0 then break;
  end;
  
end.