Define a not uniform color background

[shine world]

Hi,

Is possible to set a scene background to be transparent or set it to a fixed BMP/PNG/etc (not must change when camera position/zoom change) to obtain something like in attached image ?

Thank you very much in advance for suggestions :)

[Jerome.D (BeanzMaster)]

Hi Silverio, yes it's possible to set a fixed bitmap, i'll show you. for transparent Do you need that GLSceneViewer is transparent ?

For set a fixed bitmap as background just put a TGLHudSprite and set material texture. (you can take a look in (examples\shaders\shaderlab for a sample.

For setting GLSceneViewer background color pass thrue buffer : MyViewer.Buffer.BackgroundColor

[shine world]

Truly,
I don't understand how to place a PNG (for esample) like background of scene and so all scene is drawn on top of that without the camera/light sources touch background.

With MyViewer.Buffer.BackgroundColor actually I can change a fixed-uniform color.
I've tried with clNone but don't work and Scene isn't transparent to see below form.

[Jerome.D (BeanzMaster)]

Just set the Material.texture propertie or pass thrue material library

procedure TMainForm.LoadBackgroundImgClick(Sender: TObject);
begin
   if OpenPictureDialog.Execute then
    begin
     MaterialLibrary.LibMaterialByName('BackgroundTex').Material.Texture.Image.LoadFromFile(OpenPictureDialog.FileName);
    end;   
  end;

// background texture visible or not 
procedure TMainForm.chkBackgroundImgClick(Sender: TObject);
begin
  Button11.Enabled := chkBackgroundImg.Checked;
  ScreenBackGround.Visible := chkBackgroundImg.Checked;
  if ScreenBackGround.Visible then
    Viewer.Buffer.BackgroundColor := clBlack;

end; 

For GLSceneViewer it is actually impossible to be transparent. The solution will be render the scene in a bitmap with Transparent color as background and Blend it to a custom panelthat support transparency. If you want the scene display on transparent form. You need play with Regions.

[Jerome.D (BeanzMaster)]

Oups forgot a little screenshot :

[shine world]

Thank you very much Jerome.D.
Now I was able to get a picture how background ;)