gfxdrawpixel.pas

一个不出名的GBA模拟器

//////////////////////////////////////////////////////////////////////
//                                                                  //
// gfxDrawPixel.pas: Metacode to render a single pixel              //
//                                                                  //
// The contents of this file are subject to the Bottled Light       //
// Public License Version 1.0 (the "License"); you may not use this //
// file except in compliance with the License. You may obtain a     //
// copy of the License at http://www.bottledlight.com/BLPL/         //
//                                                                  //
// Software distributed under the License is distributed on an      //
// "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or   //
// implied. See the License for the specific language governing     //
// rights and limitations under the License.                        //
//                                                                  //
// The Original Code is the Mappy VM Core, released April 1st, 2003 //
// The Initial Developer of the Original Code is Bottled Light,     //
// Inc. Portions created by Bottled Light, Inc. are Copyright       //
// (C) 2001 - 2003 Bottled Light, Inc. All Rights Reserved.         //
//                                                                  //
// Author(s):                                                       //
//   Michael Noland (joat), [e-mail]                //
//                                                                  //
// Changelog:                                                       //
//   1.0: First public release (April 1st, 2003)                    //
//                                                                  //
//////////////////////////////////////////////////////////////////////


{$IFDEF BLEND}
    if (wins^ and (1 shl 5) <> 0) and (blendSrc and mask <> 0) then begin
      // Convert the pixel to RGB
      r := pix and $1F;
      g := (pix shr 5) and $1F;
      b := (pix shr 10) and $1F;

      // Calculate the new color
{$IFDEF FADEUP}
      r := Min(r + ((31 - r)*coeffa) shr 4, 31);
      g := Min(g + ((31 - g)*coeffa) shr 4, 31);
      b := Min(b + ((31 - b)*coeffa) shr 4, 31);
{$ENDIF}
{$IFDEF FADEDOWN}
      // Calculate the new color
      r := Max(r - (r*coeffa) shr 4, 0);
      g := Max(g - (g*coeffa) shr 4, 0);
      b := Max(b - (b*coeffa) shr 4, 0);
{$ENDIF}
{$IFDEF ABLEND}
      if blendSrc2 and ids^ <> 0 then begin
        // Unpack the 2nd color
        r2 := line^ and $1F;
        g2 := (line^ shr 5) and $1F;
        b2 := (line^ shr 10) and $1F;

        // Calculate the new color
        r := Min((r*coeffa + r2*coeffb) shr 4, 31);
        g := Min((g*coeffa + g2*coeffb) shr 4, 31);
        b := Min((b*coeffa + b2*coeffb) shr 4, 31);
      end;
{$ENDIF}

      // Repack it
      pix := r + g shl 5 + b shl 10;
    end;
{$ENDIF}

{$IFDEF OBJWIN}
    pix := sprWinData;
{$ENDIF}

    // Take care of mosaic latching
    if mclock = 0 then begin
      latch := pix;
      latchXparent := false;
      mclock := mx;
    end else begin
      Dec(mclock);
      pix := latch;
    end;

    if not latchXparent then begin
{$IFDEF OBJWIN}
      wins^ := latch;
{$ELSE}
      line^ := latch;
      ids^ := mask;
{$ENDIF}
    end;
  end else begin
    // Still take care of mosaic latching even when not visible
    if mclock = 0 then begin
      latchXparent := true;
      mclock := mx;
    end else
      Dec(mclock);
  end;

  // Step forward a touch
  Inc(wins);
  Inc(ids);
  Inc(line);