From 749c8cd11e9e6f81e93ae5ce19258431722b6bdf Mon Sep 17 00:00:00 2001
From: Tom Hughes <tom@compton.nu>
Date: Sun, 19 May 2013 16:43:25 +0100
Subject: [PATCH 10/15] Add renderer_scanline_aa_alpha
---
include/agg_pixfmt_rgba.h | 24 +++++++++++++-
include/agg_renderer_base.h | 28 ++++++++++++++++
include/agg_renderer_scanline.h | 71 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 122 insertions(+), 1 deletion(-)
diff --git a/include/agg_pixfmt_rgba.h b/include/agg_pixfmt_rgba.h
index 42f0a05..6c4bc37 100644
--- a/include/agg_pixfmt_rgba.h
+++ b/include/agg_pixfmt_rgba.h
@@ -2247,7 +2247,6 @@ namespace agg
}
-
//--------------------------------------------------------------------
void blend_color_vspan(int x, int y,
unsigned len,
@@ -2751,6 +2750,29 @@ namespace agg
}
//--------------------------------------------------------------------
+ void blend_color_hspan_alpha(int x, int y, unsigned len,
+ const color_type* colors,
+ value_type alpha,
+ const int8u* covers,
+ int8u cover)
+ {
+ value_type* p = (value_type*)m_rbuf->row_ptr(x, y, len) + (x << 2);
+ do
+ {
+ blender_type::blend_pix(m_comp_op,
+ p,
+ (colors->r * alpha + 255) >> 8,
+ (colors->g * alpha + 255) >> 8,
+ (colors->b * alpha + 255) >> 8,
+ (colors->a * alpha + 255) >> 8,
+ covers ? *covers++ : cover);
+ p += 4;
+ ++colors;
+ }
+ while(--len);
+ }
+
+ //--------------------------------------------------------------------
void blend_color_vspan(int x, int y, unsigned len,
const color_type* colors,
const int8u* covers,
diff --git a/include/agg_renderer_base.h b/include/agg_renderer_base.h
index 1808944..25f07c3 100644
--- a/include/agg_renderer_base.h
+++ b/include/agg_renderer_base.h
@@ -37,6 +37,7 @@ namespace agg
public:
typedef PixelFormat pixfmt_type;
typedef typename pixfmt_type::color_type color_type;
+ typedef typename pixfmt_type::color_type::value_type value_type;
typedef typename pixfmt_type::row_data row_data;
//--------------------------------------------------------------------
@@ -383,6 +384,33 @@ namespace agg
}
//--------------------------------------------------------------------
+ void blend_color_hspan_alpha(int x, int y, int len,
+ const color_type* colors,
+ value_type alpha,
+ const cover_type* covers,
+ cover_type cover = agg::cover_full)
+ {
+ if(y > ymax()) return;
+ if(y < ymin()) return;
+
+ if(x < xmin())
+ {
+ int d = xmin() - x;
+ len -= d;
+ if(len <= 0) return;
+ if(covers) covers += d;
+ colors += d;
+ x = xmin();
+ }
+ if(x + len > xmax())
+ {
+ len = xmax() - x + 1;
+ if(len <= 0) return;
+ }
+ m_ren->blend_color_hspan_alpha(x, y, len, colors, alpha, covers, cover);
+ }
+
+ //--------------------------------------------------------------------
void blend_color_vspan(int x, int y, int len,
const color_type* colors,
const cover_type* covers,
diff --git a/include/agg_renderer_scanline.h b/include/agg_renderer_scanline.h
index c27ca60..4fcb557 100644
--- a/include/agg_renderer_scanline.h
+++ b/include/agg_renderer_scanline.h
@@ -156,6 +156,35 @@ namespace agg
}
}
+ //================================================render_scanline_aa_alpha
+ template<class Scanline, class BaseRenderer,
+ class SpanAllocator, class SpanGenerator>
+ void render_scanline_aa_alpha(const Scanline& sl, BaseRenderer& ren,
+ SpanAllocator& alloc, SpanGenerator& span_gen,
+ unsigned alpha)
+ {
+ int y = sl.y();
+
+ unsigned num_spans = sl.num_spans();
+ typename Scanline::const_iterator span = sl.begin();
+ for(;;)
+ {
+ int x = span->x;
+ int len = span->len;
+ const typename Scanline::cover_type* covers = span->covers;
+
+ if(len < 0) len = -len;
+ typename BaseRenderer::color_type* colors = alloc.allocate(len);
+ span_gen.generate(colors, x, y, len);
+ ren.blend_color_hspan_alpha(x, y, len, colors, alpha,
+ (span->len < 0) ? 0 : covers, *covers);
+
+ if(--num_spans == 0) break;
+ ++span;
+ }
+ }
+
+
//=====================================================render_scanlines_aa
template<class Rasterizer, class Scanline, class BaseRenderer,
class SpanAllocator, class SpanGenerator>
@@ -216,8 +245,50 @@ namespace agg
};
+ //==============================================renderer_scanline_aa_alpha
+ template<class BaseRenderer, class SpanAllocator, class SpanGenerator>
+ class renderer_scanline_aa_alpha
+ {
+ public:
+ typedef BaseRenderer base_ren_type;
+ typedef SpanAllocator alloc_type;
+ typedef SpanGenerator span_gen_type;
+ //--------------------------------------------------------------------
+ renderer_scanline_aa_alpha() : m_ren(0), m_alloc(0), m_span_gen(0), m_alpha(1.0) {}
+ renderer_scanline_aa_alpha(base_ren_type& ren,
+ alloc_type& alloc,
+ span_gen_type& span_gen,
+ unsigned alpha) :
+ m_ren(&ren),
+ m_alloc(&alloc),
+ m_span_gen(&span_gen),
+ m_alpha(alpha)
+ {}
+ void attach(base_ren_type& ren,
+ alloc_type& alloc,
+ span_gen_type& span_gen)
+ {
+ m_ren = &ren;
+ m_alloc = &alloc;
+ m_span_gen = &span_gen;
+ }
+ //--------------------------------------------------------------------
+ void prepare() { m_span_gen->prepare(); }
+
+ //--------------------------------------------------------------------
+ template<class Scanline> void render(const Scanline& sl)
+ {
+ render_scanline_aa_alpha(sl, *m_ren, *m_alloc, *m_span_gen, m_alpha);
+ }
+
+ private:
+ base_ren_type* m_ren;
+ alloc_type* m_alloc;
+ span_gen_type* m_span_gen;
+ unsigned m_alpha;
+ };
//===============================================render_scanline_bin_solid
--
1.8.1.4