Merge pull request matplotlib#29450 from QuLogic/unused-resample

Remove some unused resample code

Author: tacaswell

src/_image_resample.h

@@ -519,17 +519,6 @@ struct type_mapping
         agg::pixfmt_alpha_blend_gray<blender_type, agg::rendering_buffer>,
         agg::pixfmt_alpha_blend_rgba<blender_type, agg::rendering_buffer>
     >;
-    using pixfmt_pre_type = std::conditional_t<
-        is_grayscale_v<color_type>,
-        pixfmt_type,
-        agg::pixfmt_alpha_blend_rgba<
-            std::conditional_t<
-                std::is_same_v<color_type, agg::rgba8>,
-                fixed_blender_rgba_pre<color_type, agg::order_rgba>,
-                agg::blender_rgba_pre<color_type, agg::order_rgba>
-            >,
-            agg::rendering_buffer>
-    >;
     template<typename A> using span_gen_affine_type = std::conditional_t<
         is_grayscale_v<color_type>,
         agg::span_image_resample_gray_affine<A>,

src/agg_workaround.h

@@ -8,46 +8,6 @@
  blending of RGBA32 pixels does not preserve enough precision
 */
 
-template<class ColorT, class Order>
-struct fixed_blender_rgba_pre : agg::conv_rgba_pre<ColorT, Order>
-{
-    typedef ColorT color_type;
-    typedef Order order_type;
-    typedef typename color_type::value_type value_type;
-    typedef typename color_type::calc_type calc_type;
-    typedef typename color_type::long_type long_type;
-    enum base_scale_e
-    {
-        base_shift = color_type::base_shift,
-        base_mask  = color_type::base_mask
-    };
-
-    //--------------------------------------------------------------------
-    static AGG_INLINE void blend_pix(value_type* p,
-                                     value_type cr, value_type cg, value_type cb,
-                                     value_type alpha, agg::cover_type cover)
-    {
-        blend_pix(p,
-                  color_type::mult_cover(cr, cover),
-                  color_type::mult_cover(cg, cover),
-                  color_type::mult_cover(cb, cover),
-                  color_type::mult_cover(alpha, cover));
-    }
-
-    //--------------------------------------------------------------------
-    static AGG_INLINE void blend_pix(value_type* p,
-                                     value_type cr, value_type cg, value_type cb,
-                                     value_type alpha)
-    {
-        alpha = base_mask - alpha;
-        p[Order::R] = (value_type)(((p[Order::R] * alpha) >> base_shift) + cr);
-        p[Order::G] = (value_type)(((p[Order::G] * alpha) >> base_shift) + cg);
-        p[Order::B] = (value_type)(((p[Order::B] * alpha) >> base_shift) + cb);
-        p[Order::A] = (value_type)(base_mask - ((alpha * (base_mask - p[Order::A])) >> base_shift));
-    }
-};
-
-
 template<class ColorT, class Order>
 struct fixed_blender_rgba_plain : agg::conv_rgba_plain<ColorT, Order>
 {