Glow, Blur in 2d with no opengl or d3d ? possible ?

[Andreaz]

Use Bitmap.Scanline instead of Bitmap.Canvas.Pixels[ x,y ] and you'll jump alot in speed;

The following code is to convert a Phoenix texture to a windows Bitmap showing the use of scanline:

Type TRGBQuadArray = Array[WORD] of TRGBQuad;
Type PRGBQuadArray = ^TRGBQuadArray;
Type TRGBTripleArray = Array[WORD] of TRGBTriple;
Type PRGBTripleArray = ^TRGBTripleArray;

var Line   : PRGBTripleArray;
var X,Y    : Integer;
var Color  : TColor4b;
begin
  Dest.Width      := Source.Width;
  Dest.Height     := Source.Height;
  Dest.PixelFormat:= Graphics.pf24Bit;

  For Y:=0 to Source.Height-1 do begin
    Line:=Dest.ScanLine[Y];
    For X:=0 to Source.Width-1 do begin
      Color:= Source.Pixels[X,Y];

      Line[X].rgbtRed     := Color.Red  ;
      Line[X].rgbtGreen   := Color.Green;
      Line[X].rgbtBlue    := Color.Blue ;
    end;
  end;

[arthurprs]

Use Bitmap.Scanline instead of Bitmap.Canvas.Pixels[ x,y ] and you'll jump alot in speed;

The following code is to convert a Phoenix texture to a windows Bitmap showing the use of scanline:

Type TRGBQuadArray = Array[WORD] of TRGBQuad;
Type PRGBQuadArray = ^TRGBQuadArray;
Type TRGBTripleArray = Array[WORD] of TRGBTriple;
Type PRGBTripleArray = ^TRGBTripleArray;

var Line   : PRGBTripleArray;
var X,Y    : Integer;
var Color  : TColor4b;
begin
  Dest.Width      := Source.Width;
  Dest.Height     := Source.Height;
  Dest.PixelFormat:= Graphics.pf24Bit;

  For Y:=0 to Source.Height-1 do begin
    Line:=Dest.ScanLine[Y];
    For X:=0 to Source.Width-1 do begin
      Color:= Source.Pixels[X,Y];

      Line[X].rgbtRed     := Color.Red  ;
      Line[X].rgbtGreen   := Color.Green;
      Line[X].rgbtBlue    := Color.Blue ;
    end;
  end;

I will try =]

[jasonf]

Also, Cache your results wherever possible, don't regenerate glows for images you've already generated glows for.

To speed the process up, if you have a small number of sprites, you could generate glows for all of your sprites before the game begins.. or generate and cache them as you go if you have more.

By doing this, you, and not making your glows for every render, you'll improve your performance enormously.

How you implement your cache system is up to you though, I could suggest something, but it might be incompatible with your game engine.

[arthurprs]

Also, Cache your results wherever possible, don't regenerate glows for images you've already generated glows for.

To speed the process up, if you have a small number of sprites, you could generate glows for all of your sprites before the game begins.. or generate and cache them as you go if you have more.

By doing this, you, and not making your glows for every render, you'll improve your performance enormously.

How you implement your cache system is up to you though, I could suggest something, but it might be incompatible with your game engine.

Suggest

[jasonf]

Well, one way would be to use a list of some type, something which gives you access to objects contained within using a key. I use a TStringList

Then, all you need to do is.

1. Drawing routine wants to draw a glow for sprite named "MAN"

2. Check GlowCache (aformentioned list), If glowsurface exists, return it.

2.1 If glow surface does not exist, render the glow to a new surface for the sprite named "MAN" and add the glow to the cache with the key of "MAN", return it.

3. Render the glow to the destination surface.


From this point on, all calls for a glow for the sprite "MAN" will return a pre-generated glow.