Offset filter

(bzr r9508.1.18)

3 files changed, 22 insertions, 29 deletions

diff --git a/src/display/nr-filter-blend.cpp b/src/display/nr-filter-blend.cpp
index 758b49fe4..8a1cfa6f4 100644
--- a/src/display/nr-filter-blend.cpp
+++ b/src/display/nr-filter-blend.cpp
@@ -159,6 +159,7 @@ void surface_blend(cairo_surface_t *in1, cairo_surface_t *in2, cairo_surface_t *
     // WARNING: code below assumes that:
     // 1. Cairo ARGB32 surface strides are always divisible by 4
     // 2. We can only receive CAIRO_FORMAT_ARGB32 or CAIRO_FORMAT_A8 surfaces
+    // 3. Both surfaces are of the same size
 
     int w = cairo_image_surface_get_width(in2);
     int h = cairo_image_surface_get_height(in2);
diff --git a/src/display/nr-filter-offset.cpp b/src/display/nr-filter-offset.cpp
index fd4f55053..b44c5fac7 100644
--- a/src/display/nr-filter-offset.cpp
+++ b/src/display/nr-filter-offset.cpp
@@ -9,11 +9,10 @@
  * Released under GNU GPL, read the file 'COPYING' for more information
  */
 
+#include "display/cairo-utils.h"
 #include "display/nr-filter-offset.h"
 #include "display/nr-filter-slot.h"
 #include "display/nr-filter-units.h"
-#include "libnr/nr-blit.h"
-#include "libnr/nr-pixblock.h"
 #include "libnr/nr-rect-l.h"
 
 namespace Inkscape {
@@ -33,37 +32,29 @@ FilterPrimitive * FilterOffset::create() {
 FilterOffset::~FilterOffset()
 {}
 
-int FilterOffset::render(FilterSlot &slot, FilterUnits const &units) {
-    NRPixBlock *in = slot.get(_input);
-    // Bail out if source image is missing
-    if (!in) {
-        g_warning("Missing source image for feOffset (in=%d)", _input);
-        return 1;
-    }
-
-    NRPixBlock *out = new NRPixBlock;
+void FilterOffset::render_cairo(FilterSlot &slot)
+{
+    cairo_surface_t *in = slot.getcairo(_input);
+    cairo_surface_t *out = ink_cairo_surface_create_identical(in);
+    cairo_t *ct = cairo_create(out);
 
-    Geom::Matrix trans = units.get_matrix_primitiveunits2pb();
+    Geom::Matrix trans = slot.get_units().get_matrix_primitiveunits2pb();
     Geom::Point offset(dx, dy);
     offset *= trans;
     offset[X] -= trans[4];
     offset[Y] -= trans[5];
 
-    nr_pixblock_setup_fast(out, in->mode,
-                           in->area.x0, in->area.y0, in->area.x1, in->area.y1,
-                           true);
-    nr_blit_pixblock_pixblock(out, in);
+    cairo_set_source_surface(ct, in, offset[X], offset[Y]);
+    cairo_paint(ct);
+    cairo_destroy(ct);
 
-    out->area.x0 += static_cast<NR::ICoord>(offset[X]);
-    out->area.y0 += static_cast<NR::ICoord>(offset[Y]);
-    out->area.x1 += static_cast<NR::ICoord>(offset[X]);
-    out->area.y1 += static_cast<NR::ICoord>(offset[Y]);
-    out->visible_area = out->area;
-
-    out->empty = FALSE;
     slot.set(_output, out);
+    cairo_surface_destroy(out);
+}
 
-    return 0;
+bool FilterOffset::can_handle_affine(Geom::Matrix const &)
+{
+    return true;
 }
 
 void FilterOffset::set_dx(double amount) {
@@ -82,15 +73,15 @@ void FilterOffset::area_enlarge(NRRectL &area, Geom::Matrix const &trans)
     offset[Y] -= trans[5];
 
     if (offset[X] > 0) {
-        area.x0 -= static_cast<NR::ICoord>(offset[X]);
+        area.x0 -= ceil(offset[X]);
     } else {
-        area.x1 -= static_cast<NR::ICoord>(offset[X]);
+        area.x1 -= floor(offset[X]);
     }
 
     if (offset[Y] > 0) {
-        area.y0 -= static_cast<NR::ICoord>(offset[Y]);
+        area.y0 -= ceil(offset[Y]);
     } else {
-        area.y1 -= static_cast<NR::ICoord>(offset[Y]);
+        area.y1 -= floor(offset[Y]);
     }
 }
 
diff --git a/src/display/nr-filter-offset.h b/src/display/nr-filter-offset.h
index b00ad25fe..8404aa3d9 100644
--- a/src/display/nr-filter-offset.h
+++ b/src/display/nr-filter-offset.h
@@ -26,8 +26,9 @@ public:
     static FilterPrimitive *create();
     virtual ~FilterOffset();
 
-    virtual int render(FilterSlot &slot, FilterUnits const &units);
+    virtual void render_cairo(FilterSlot &slot);
     virtual void area_enlarge(NRRectL &area, Geom::Matrix const &trans);
+    virtual bool can_handle_affine(Geom::Matrix const &);
 
     void set_dx(double amount);
     void set_dy(double amount);