freepascal.compiler/packages/libndsfpc/examples/graphics/3D/Ortho/Ortho.pp

program Ortho;
{$L build/drunkenlogo.pcx.o}

{$mode objfpc}

uses
  ctypes, nds9;

{$include inc/drunkenlogo.pcx.inc}

var
  xrot: cfloat;       // X Rotation
  yrot: cfloat;       // Y Rotation
  zrot: cfloat;       // Z Rotation

  texture: array [0..0] of cint;      // Storage For One Texture

// Load PCX files And Convert To Textures
function LoadGLTextures(): boolean;
var
  pcx: sImage;
begin
  //load our texture
  loadPCX(pcuint8(drunkenlogo_pcx), @pcx);

  image8to16(@pcx);

  glGenTextures(1, @texture[0]);
  glBindTexture(0, texture[0]);
  glTexImage2D(0, 0, GL_RGB, 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
begin
  glTranslatef(0.0,0.0,-5.0);

  glRotatef(xrot,1.0,0.0,0.0);
  glRotatef(yrot,0.0,1.0,0.0);
  glRotatef(zrot,0.0,0.0,1.0);

  glBindTexture(GL_TEXTURE_2D, texture[0]);

  glBegin(GL_QUADS);
    // Front Face
    glTexCoord2f(0.0, 0.0); glVertex3f(-1.0, -1.0,  1.0);
    glTexCoord2f(1.0, 0.0); glVertex3f( 1.0, -1.0,  1.0);
    glTexCoord2f(1.0, 1.0); glVertex3f( 1.0,  1.0,  1.0);
    glTexCoord2f(0.0, 1.0); glVertex3f(-1.0,  1.0,  1.0);
    // Back Face
    glTexCoord2f(1.0, 0.0); glVertex3f(-1.0, -1.0, -1.0);
    glTexCoord2f(1.0, 1.0); glVertex3f(-1.0,  1.0, -1.0);
    glTexCoord2f(0.0, 1.0); glVertex3f( 1.0,  1.0, -1.0);
    glTexCoord2f(0.0, 0.0); glVertex3f( 1.0, -1.0, -1.0);
    // Top Face
    glTexCoord2f(0.0, 1.0); glVertex3f(-1.0,  1.0, -1.0);
    glTexCoord2f(0.0, 0.0); glVertex3f(-1.0,  1.0,  1.0);
    glTexCoord2f(1.0, 0.0); glVertex3f( 1.0,  1.0,  1.0);
    glTexCoord2f(1.0, 1.0); glVertex3f( 1.0,  1.0, -1.0);
    // Bottom Face
    glTexCoord2f(1.0, 1.0); glVertex3f(-1.0, -1.0, -1.0);
    glTexCoord2f(0.0, 1.0); glVertex3f( 1.0, -1.0, -1.0);
    glTexCoord2f(0.0, 0.0); glVertex3f( 1.0, -1.0,  1.0);
    glTexCoord2f(1.0, 0.0); glVertex3f(-1.0, -1.0,  1.0);
    // Right face
    glTexCoord2f(1.0, 0.0); glVertex3f( 1.0, -1.0, -1.0);
    glTexCoord2f(1.0, 1.0); glVertex3f( 1.0,  1.0, -1.0);
    glTexCoord2f(0.0, 1.0); glVertex3f( 1.0,  1.0,  1.0);
    glTexCoord2f(0.0, 0.0); glVertex3f( 1.0, -1.0,  1.0);
    // Left Face
    glTexCoord2f(0.0, 0.0); glVertex3f(-1.0, -1.0, -1.0);
    glTexCoord2f(1.0, 0.0); glVertex3f(-1.0, -1.0,  1.0);
    glTexCoord2f(1.0, 1.0); glVertex3f(-1.0,  1.0,  1.0);
    glTexCoord2f(0.0, 1.0); glVertex3f(-1.0,  1.0, -1.0);
  glEnd();

  xrot := xrot + 0.3;
  yrot := yrot + 0.2;
  zrot := zrot + 0.4;
  result := true;
end;

var
  held: integer;

begin
  // Setup the Main screen for 3D
  videoSetMode(MODE_0_3D);
  vramSetBankA(VRAM_A_TEXTURE); // reserve some memory for textures

  // initialize gl
  glInit();

  //enable textures
  glEnable(GL_TEXTURE_2D);

  // 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);

  glLight(0, RGB15(31,31,31) , 0, floattov10(-1.0),                0);
  glLight(1, RGB15(31,31,31) , 0,                0, floattov10(-1.0));
  glLight(2, RGB15(31,31,31) , 0,                0, floattov10( 1.0));

  glMatrixMode(GL_TEXTURE);
  glLoadIdentity();

  glMatrixMode(GL_MODELVIEW);

  //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();

  // Set our viewport to be the same size as the screen
  glViewport(0,0,255,191);

  LoadGLTextures();

  // set the vertex color to white
  glColor3f(1,1,1);

  while true do
  begin
    scanKeys();
    held := keysHeld();

    //reset the projection matrix
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();

    // set the projection matrix as either ortho or perspective
    if (held and KEY_R) = 0 then
      gluPerspective(70, 256.0 / 192.0, 0.1, 100)
    else
      glOrtho(-3, 3,-2, 2, 0.1, 100);

    // Set the current matrix to be the model matrix
    glMatrixMode(GL_MODELVIEW);

    //ds specific, several attributes can be set here
    if (held and KEY_L) <> 0 then
      glPolyFmt(POLY_ALPHA(0) or POLY_CULL_NONE or POLY_FORMAT_LIGHT0 or POLY_FORMAT_LIGHT1 or POLY_FORMAT_LIGHT2)
    else
      glPolyFmt(POLY_ALPHA(31) or POLY_CULL_NONE or POLY_FORMAT_LIGHT0 or POLY_FORMAT_LIGHT1 or POLY_FORMAT_LIGHT2);


    //Push our original Matrix onto the stack (save state)
    glPushMatrix();

    DrawGLScene();

    // Pop our Matrix from the stack (restore state)
    glPopMatrix(1);

    // flush to screen
    glFlush(0);
    
    if (held and KEY_START) <> 0 then break;
  end;
end.