- completely clear all texture data when setting a frame size.

SMK tries to draw a texture from it before the first frame has been rendered. This ensures that it gets a fully black frame.
Fixes #167.

source/common/textures/animtexture.cpp

@@ -47,6 +47,7 @@ void AnimTexture::SetFrameSize(int  format, int width, int height)
     FTexture::SetSize(width, height);
     Image.Resize(width * height * (format == Paletted ? 1 : 3));
     memset(Image.Data(), 0, Image.Size());
+    CleanHardwareTextures();
     pixelformat = format;
 }
 

source/core/screenjob.cpp

@@ -315,6 +315,7 @@ public:
 	{
 		Smacker_Close(hSMK);
 		soundEngine->StopAllChannels();
+		animtex.Clean();
 	}
 };