Get an SIGSEGV error when add a PNGImage in TGLCompositeImage

Question

I am usings Lazarus 1.2.4 and GLSCENE svn 6462 (1.2 svn version)

I add material with this function below

function AddMaterial(aMatLib: TGlMaterialLibrary; aFileName, aMaterialName: string):     TGlLibMaterial; overload;
  begin
    result := aMatLib.Materials.Add;
    with result do
      begin
        with Material do
          begin
            if aFileName= 'Fast_Blur' then
              begin
                MaterialOptions:= [moNoLighting];
                Texture.Disabled:= true;
                Texture.TextureMode:= tmDecal;
                BlendingMode:= bmModulate;
              end
            else
              begin
                MaterialOptions := [moIgnoreFog, moNoLighting];
                Texture.Disabled := false;
                Texture.TextureMode:= tmModulate;
                BlendingMode := bmTransparency;
              end;
         with FrontProperties do
           begin
             Ambient.SetColor(1, 1, 1, 1);
             if aFileName= 'Fast_Blur' then
              Diffuse.SetColor(204,204,204,1)
             else
              Diffuse.SetColor(1, 1, 1, 1);
             Emission.SetColor(1, 1, 1, 1);
             Specular.SetColor(1, 1, 1, 1);
           end;
     Texture.ImageClassName:= 'TGLCompositeImage';

       if aFileName<> 'Fast_Blur' then
         begin
           if ExtractFileExt(aFileName) = '.bmp' then
             TGLCompositeImage(Texture.Image).LoadFromFile(aFileName)
         else if ExtractFileExt(aFileName) = '.tga' then
            begin
              TGLCompositeImage(Texture.Image).LoadFromFile(aFileName);
            end
         else if ExtractFileExt(aFileName) = '' then
           TGLCompositeImage(Texture.Image).LoadFromFile(aFileName + '.png');
     end;
  end;
  Name := aMaterialName;
  end;
end;

When i run it i get the below error

Project One raised exception class "External : SIGSEGV"

Try some digging find that when the pngimage try to load from stream in line

177

CODE
 if _png_sig_cmp(@sig, 0, 8) <> 0 then

And before execute the raise EInvalidRasterFile.Create('Invalid PNG file');

get the SIGSEGV..

So anybody can help ...

Ps... if i change the TGLComposite image with TGLPictureImage then works perfect but i dont have the Transparency of the images..

Ps2... After more digging i found that all errors comes from the external LIBPNG so not work well together GLPNGFILE and LIBPNG

score 1 · Answer 1 · answered Oct 11 '14 at 10:57

1

My settings for *.png textures:

class Name: TGLCompositeImage
alpha: tiaDefault
texture mode: tmAdd

answered Oct 11 '14 at 10:57

mobilus

46
1

The settings is OK when i work with delphi 7 and yours too... but i think here the problem is the Lazarus itself ... thank you so much – azrael11 Oct 11 '14 at 11:15

Get an SIGSEGV error when add a PNGImage in TGLCompositeImage

1 Answers1