Procedure SwapY(Var Pixels : pBytes; xSize,ySize : Integer);

Type

TRGB = record

R,G,B,A : Byte;

end;

Var

Temp : array of array of TRGB;

x,y,c : integer;

begin

 

SetLength(Temp,xSize,ySize);

c := -1;

for x := 0 to xSize-1 do

for y := 1 to ySize do

begin

Inc(c);

Temp[x,ySize-y].R := Pixels[c];

Inc(c);

Temp[x,ySize-y].G := Pixels[c];

Inc(c);

Temp[x,ySize-y].B := Pixels[c];

Inc(c);

Temp[x,ySize-y].A := Pixels[c];

end;

 

c := -1;

 

for x := 0 to xSize-1 do

for y := 0 to ySize-1 do

begin

Inc(c);

Pixels[c] := Temp[x,y].R;

Inc(c);

Pixels[c] := Temp[x,y].G;

Inc(c);

Pixels[c] := Temp[x,y].B;

Inc(c);

Pixels[c] := Temp[x,y].A;

end;

 

SetLength(Temp,0,0);

 

end;

 

function LoadDDS(Stream: TStream; Var Texture : Cardinal; Const NoPicMip : Boolean; Var Width,Height : Integer): boolean;

var

  hdr: TDDSHeader;

  mipMapCount, x, y, xSize, ySize: Cardinal;

  li: ^TDDSLoadInfo;

  data,pixels: PBytes;

  unpacked: PGLuints;

  size, ix, zz: Cardinal;

  palette: array[0..255] of Cardinal;

begin

  result := false;

  //  DDS is so simple to read, too

  Stream.Read(hdr, sizeof(hdr));

  if (hdr.dwMagic<>DDS_MAGIC) or (hdr.dwSize<>124) or

     ((hdr.dwFlags and DDSD_PIXELFORMAT)=0) or ((hdr.dwFlags and DDSD_CAPS)=0) then exit;

 

  if (addr(glTexParameteri)=NIL) or

     (addr(glCompressedTexImage2D)=NIL) or

     (addr(glPixelStorei)=NIL) then exit;

  xSize := hdr.dwWidth;

  ySize := hdr.dwHeight;

 

  if (PF_IS_DXT1(hdr.PixelFormat)) then li := @loadInfoDXT1 else

  if (PF_IS_DXT3(hdr.PixelFormat)) then li := @loadInfoDXT3 else

  if (PF_IS_DXT5(hdr.PixelFormat)) then li := @loadInfoDXT5 else

  if (PF_IS_BGRA8(hdr.PixelFormat)) then li := @loadInfoBGRA8 else

  if (PF_IS_BGR8(hdr.PixelFormat)) then li := @loadInfoBGR8 else

  if (PF_IS_BGR5A1(hdr.PixelFormat)) then li := @loadInfoBGR5A1 else

  if (PF_IS_BGR565(hdr.PixelFormat)) then li := @loadInfoBGR565 else

  if (PF_IS_INDEX8(hdr.PixelFormat)) then li := @loadInfoIndex8 else

  exit;

 

  x := xSize;

  y := ySize;

  Width := x;

  Height := y;

  GetMem(pixels, xSize*ySize*4);

 

 

  glGenTextures(1, @Texture);

  glBindTexture(GL_TEXTURE_2D, Texture);

 

  glEnable(GL_TEXTURE_2D);

 

//  glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);  {Texture blends with object background}

 

  if NoPicMip then begin

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);

  end

  else begin

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

  end;

 

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);

 

{$IFDEF GL_14}

  if GL_14 then

    glTexParameteri(GL_TEXTURE_2D, GL_GENERATE_MIPMAP, GL_FALSE);

{$ENDIF}

  if hdr.dwFlags and DDSD_MIPMAPCOUNT<>0 then mipMapCount := hdr.dwMipMapCount else mipMapCount := 1;

 

  if li.compressed then begin

    size := max(li.divSize, x ) div li.divSize * max(li.divSize, y) div li.divSize * li.blockBytes;

    GetMem(data, size);

    for ix:=0 to mipMapCount-1 do begin

      Stream.Read(data^, size);

      glCompressedTexImage2D(GL_TEXTURE_2D, ix, li.internalFormat, x, y, 0, size, data);

      glGetTexImage(GL_TEXTURE_2D, ix, GL_RGBA, GL_BYTE, pixels);

      SwapY(pixels,xSize,ySize);

      glTexImage2D(GL_TEXTURE_2D, ix, GL_RGBA, xsize, ysize, 0, GL_RGBA, GL_BYTE, pixels);

      x := (x+1) shr 1;

      y := (y+1) shr 1;

      size := max(li.divSize, x ) div li.divSize * max(li.divSize, y ) div li.divSize * li.blockBytes;

    end;

    FreeMem(data);

  end

  else if li.palette then begin

    size := hdr.dwPitchOrLinearSize * ySize;

    GetMem(data, size);

    GetMem(unpacked, size * sizeof(cardinal));

    Stream.Read(palette, 1024);

    for ix:=0 to mipMapCount-1 do begin

      Stream.Read(data^, size);

      for zz:=0 to size-1 do

        unpacked[zz] := palette[data[zz]];

      glPixelStorei(GL_UNPACK_ROW_LENGTH, y);

      glTexImage2D(GL_TEXTURE_2D, ix, li.internalFormat, x, y, 0, li.externalFormat, li.typ, unpacked);

      glGetTexImage(GL_TEXTURE_2D, ix, GL_RGBA, GL_BYTE, pixels);

      SwapY(pixels,xSize,ySize);

      glTexImage2D(GL_TEXTURE_2D, ix, GL_RGBA, xsize, ysize, 0, GL_RGBA, GL_BYTE, pixels);

      x := (x+1) shr 1;

      y := (y+1) shr 1;

      size := x * y * li.blockBytes;

    end;

    FreeMem(data);

    FreeMem(unpacked);

  end

  else begin

    if li.swap then

      glPixelStorei(GL_UNPACK_SWAP_BYTES, GL_TRUE);

    size := x * y * li.blockBytes;

    GetMem(data, size);

    for ix:=0 to mipMapCount-1 do begin

      Stream.Read(data^, size);

      glPixelStorei(GL_UNPACK_ROW_LENGTH, y);

      glTexImage2D(GL_TEXTURE_2D, ix, li.internalFormat, x, y, 0, li.externalFormat, li.typ, data);

      glGetTexImage(GL_TEXTURE_2D, ix, GL_RGBA, GL_BYTE, pixels);

      SwapY(pixels,xSize,ySize);

      glTexImage2D(GL_TEXTURE_2D, ix, GL_RGBA, xsize, ysize, 0, GL_RGBA, GL_BYTE, pixels);

      x := (x+1) shr 1;

      y := (y+1) shr 1;

      size := x * y * li.blockBytes;

    end;

    FreeMem(data);

    glPixelStorei(GL_UNPACK_SWAP_BYTES, GL_FALSE);

  end;

{$IFDEF GL_12}

  if GL_12 then

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, mipMapCount-1);

{$ENDIF}

  FreeMem(pixels);

 

  result := true;

end;

 

 

Procedure SwapY(Pixels: pBytes; xSize, ySize: Integer);

var x, y: integer;

    P1, P2: ^Cardinal;

    Temp: Cardinal;

begin

  for y:=0 to Pred(ySize shr 1) do

    for x:=0 to Pred(xSize) do begin

      P1 := Addr(Pixels^[(y*xSize + x)*4]);

      P2 := Addr(Pixels^[((ySize-y-1)*xSize + x)*4]);

      Temp := P1^;

      P1^ := P2^;

      P2^ := Temp;

    end;

end;