How to use "Painter" Struct?

[hinohie]

Currently, "Painter" doesn't have any member values. I want to give something to him

Case 1:
Make every Draw functions to static, and Painter itself just contained some property map.
and Draw function use that properties.

This case, we don't need to make some values for Painter .

struct Painter
{
  using PropertyMap = std::map<PropertyType, PropertyValue>;
  PropertyMap mProperties;

  // draw utils
  void Draw(Image img, ~~~) { Draw(~~, mProperties); }

  // static draw utils
  static void Draw(Image img, ~~~ , const PropertyMap& properties = PropertyMap());
}

Case 2:
Make some BasePainterInterface and class Painter : public BasePainterInterface.
This case, we can generate custom painters easy.

struct BasePainterInterface {
  void Draw(Image img, ~~~) = 0;
}
struct MaskingPainterInterface {
  void Draw(Image img, Image masking, ~~~) = 0;
}
struct VectorImagePainterInterface {
  void Draw(VectorImage img, ~~~) = 0;
}

struct Painter : public BasePainterInterface, public MaskingPainterInterface {
  void Draw(~~) override;
}
struct VectorPainter : public BasePainterInterface, public VectorImagePainterInterface {
  void Draw(~~) override;
}

[tallua]

What I thought for the Painter struct was just dividing drawing logics from the image, so the above case was not considered.
As we are not currently using Painter, I think it is a good time to re-design Painter struct.

For re-designing, we need to consider some points on drawing logics.

1. Currently, Painter considers 'where to draw' and 'what color' it will use.
   The feature you wants to add is Masking and Vector, which modifies 'where to draw' feature.
   And Painter already have modifying 'what color' feature (declared separately Draw(..., Line, ...) and DrawGradient(..., Line, ....)).
   I think it will be better to separate those two for better usage.

2. As mentioned above, Painter only considers 'where to draw' and 'what color' it will use.
   Will there be other features added in future except modifying 'where to draw' and 'what color' features?
   If so, what will be those features?

3. On Case2 you mentioned, you used virtual functions, and it will use dynamic dispatch.
   Is it worth to reduce Performance?

[hinohie]

I don't care about performance issue. Because it is just toy.. Not Samsung project >ㅅ<

[hinohie]

painter.Draw( Where, What shape, What color, How(if need));
is the basic logic of Painter I think.
and the How (something like AlphaBehavior or SamplingMode, or Border options) can be the member of painter