[gegl/soc-2013-n-point-deformation: 17/28] npd: add option to draw mesh

[Marek Dvoroznak <dvoromar src gnome org>]

commit 574b679bf5271bf4a395af86f36116fe007c32ee
Author: Marek Dvoroznak <dvoromar gmail com>
Date:   Sun Aug 18 20:38:29 2013 +0200

    npd: add option to draw mesh

 libs/npd/graphics.c             |   22 +++++++++++++
 libs/npd/graphics.h             |    7 ++++
 libs/npd/npd_common.h           |    5 ++-
 operations/external/Makefile.am |    6 ++-
 operations/external/npd.c       |   65 +++++++++++++++++++++++++++++++--------
 5 files changed, 88 insertions(+), 17 deletions(-)
---
diff --git a/libs/npd/graphics.c b/libs/npd/graphics.c
index ef0644d..57a580c 100644
--- a/libs/npd/graphics.c
+++ b/libs/npd/graphics.c
@@ -131,6 +131,28 @@ npd_create_mesh_from_image (NPDModel *model,
   g_ptr_array_free(reference_bones, TRUE);
 }
 
+void npd_draw_mesh (NPDModel   *model,
+                    NPDDisplay *display)
+{
+  NPDHiddenModel *hm = model->hidden_model;
+  gint i, j;
+
+  for (i = 0; i < hm->num_of_bones; i++)
+    {
+      NPDBone  *bone  = &hm->current_bones[i];
+      NPDPoint *first = &bone->points[0];
+      NPDPoint *p0, *p1;
+
+      for (j = 1; j < bone->num_of_points; j++)
+        {
+          p0 = &bone->points[j - 1];
+          p1 = &bone->points[j];
+          npd_draw_line (display, p0->x, p0->y, p1->x, p1->y);
+        }
+      npd_draw_line (display, p1->x, p1->y, first->x, first->y);
+    }
+}
+
 gboolean
 npd_compare_colors (NPDColor *c1,
                     NPDColor *c2)
diff --git a/libs/npd/graphics.h b/libs/npd/graphics.h
index ba1c8f7..02d2745 100644
--- a/libs/npd/graphics.h
+++ b/libs/npd/graphics.h
@@ -39,6 +39,8 @@ void        npd_create_mesh_from_image        (NPDModel   *model,
                                                gint        position_y);
 void        npd_draw_model                    (NPDModel   *model,
                                                NPDDisplay *display);
+void        npd_draw_mesh                     (NPDModel   *model,
+                                               NPDDisplay *display);
 
 gboolean    npd_load_image                    (NPDImage   *image,
                                                const char *path);
@@ -63,6 +65,11 @@ void        npd_draw_texture_line             (gint        x1,
                                                NPDMatrix  *A,
                                                NPDImage   *input_image,
                                                NPDImage   *output_image);
+void      (*npd_draw_line)                    (NPDDisplay *display,
+                                               gfloat      x0,
+                                               gfloat      y0,
+                                               gfloat      x1,
+                                               gfloat      y1);
 gint        npd_bilinear_interpolation        (gint        I0,
                                                gint        I1,
                                                gint        I2,
diff --git a/libs/npd/npd_common.h b/libs/npd/npd_common.h
index e99350a..2433f17 100644
--- a/libs/npd/npd_common.h
+++ b/libs/npd/npd_common.h
@@ -92,9 +92,10 @@ typedef struct
   NPDDisplay           *display;
 } NPDModel;
 
-#define npd_init(set_pixel, get_pixel)\
+#define npd_init(set_pixel, get_pixel, draw_line)\
 npd_set_pixel_color = set_pixel;\
-npd_get_pixel_color = get_pixel
+npd_get_pixel_color = get_pixel;\
+npd_draw_line       = draw_line
 
 void             npd_init_model                 (NPDModel        *model);
 void             npd_destroy_hidden_model       (NPDHiddenModel  *model);
diff --git a/operations/external/Makefile.am b/operations/external/Makefile.am
index 1d86ee0..6b2dc4f 100644
--- a/operations/external/Makefile.am
+++ b/operations/external/Makefile.am
@@ -159,10 +159,12 @@ rgbe_save_la_CFLAGS = $(AM_CFLAGS) -I $(top_srcdir)/libs
 rgbe_save_la_LIBADD = $(op_libs) $(top_builddir)/libs/rgbe/librgbe.la
 
 # Dependencies are in our source tree
+if HAVE_CAIRO
 ops += npd.la
 npd_la_SOURCES = npd.c
-npd_la_CFLAGS = $(AM_CFLAGS) $(NPD_CFLAGS)
-npd_la_LIBADD = $(op_libs) $(NPD_LIBS)
+npd_la_CFLAGS = $(AM_CFLAGS) $(NPD_CFLAGS) $(CAIRO_CFLAGS)
+npd_la_LIBADD = $(op_libs) $(NPD_LIBS) $(CAIRO_LIBS)
+endif
 
 opdir = $(libdir)/gegl- GEGL_API_VERSION@
 op_LTLIBRARIES = $(ops)
diff --git a/operations/external/npd.c b/operations/external/npd.c
index 47839b1..1b700a8 100644
--- a/operations/external/npd.c
+++ b/operations/external/npd.c
@@ -33,7 +33,7 @@ gegl_chant_int     (rigidity,    _("rigidity"),
 
 gegl_chant_boolean (ASAP_deformation, _("ASAP deformation"),
                     FALSE,
-                    _("ASAP deformation is performend when TRUE, ARAP deformation otherwise"))
+                    _("ASAP deformation is performed when TRUE, ARAP deformation otherwise"))
 
 gegl_chant_boolean (MLS_weights, _("MLS weights"),
                     FALSE,
@@ -42,6 +42,10 @@ gegl_chant_boolean (MLS_weights, _("MLS weights"),
 gegl_chant_double  (MLS_weights_alpha, _("MLS weights alpha"),
                     0.1, 2.0, 1.0,
                     _("Alpha parameter of MLS weights"))
+
+gegl_chant_boolean (mesh_visible, _("mesh visible"),
+                    TRUE,
+                    _("Should the mesh be visible?"))
 #else
 
 #define GEGL_CHANT_TYPE_FILTER
@@ -52,6 +56,7 @@ gegl_chant_double  (MLS_weights_alpha, _("MLS weights alpha"),
 #include <math.h>
 #include <npd/npd.h>
 #include <npd/npd_gegl.h>
+#include <cairo.h>
 
 struct _NPDImage
 {
@@ -63,13 +68,14 @@ struct _NPDImage
 
 struct _NPDDisplay
 {
-  NPDImage image;
+  NPDImage  image;
+  cairo_t  *cr;
 };
 
 typedef struct
 {
-  gboolean first_run;
-  NPDModel model;
+  gboolean  first_run;
+  NPDModel  model;
 } NPDProperties;
 
 void npd_create_image         (NPDImage   *image,
@@ -86,6 +92,11 @@ void npd_get_pixel_color_impl (NPDImage *image,
                                gint      y,
                                NPDColor *color);
 
+void npd_draw_line_impl       (NPDDisplay *display,
+                               gfloat      x0,
+                               gfloat      y0,
+                               gfloat      x1,
+                               gfloat      y1);
 
 void npd_set_pixel_color_impl (NPDImage *image,
                                gint      x,
@@ -126,25 +137,52 @@ npd_get_pixel_color_impl (NPDImage *image,
     }
 }
 
+void npd_draw_line_impl (NPDDisplay *display,
+                         gfloat      x0,
+                         gfloat      y0,
+                         gfloat      x1,
+                         gfloat      y1)
+{
+  cairo_move_to (display->cr, x0, y0);
+  cairo_line_to (display->cr, x1, y1);
+}
+
 void
 npd_draw_model (NPDModel   *model,
                 NPDDisplay *display)
 {
-  NPDHiddenModel *hidden_model = model->hidden_model;
+  NPDHiddenModel *hm = model->hidden_model;
   NPDImage *image = model->reference_image;
   gint i;
 
   /* draw texture */
   if (model->texture_visible)
     {
-      for (i = 0; i < hidden_model->num_of_bones; i++)
+      for (i = 0; i < hm->num_of_bones; i++)
         {
-          npd_texture_quadrilateral(&hidden_model->reference_bones[i],
-                                    &hidden_model->current_bones[i],
+          npd_texture_quadrilateral(&hm->reference_bones[i],
+                                    &hm->current_bones[i],
                                      image,
                                     &display->image);
         }
     }
+  
+  /* draw mesh */
+  if (model->mesh_visible)
+    {
+      cairo_surface_t *surface;
+
+      surface = cairo_image_surface_create_for_data (display->image.buffer,
+                                                     CAIRO_FORMAT_ARGB32,
+                                                     display->image.width,
+                                                     display->image.height,
+                                                     display->image.width * 4);
+      display->cr = cairo_create (surface);
+      cairo_set_line_width (display->cr, 1);
+      cairo_set_source_rgba (display->cr, 0, 0, 0, 1);
+      npd_draw_mesh (model, display);
+      cairo_stroke (display->cr);
+    }
 }
 
 void
@@ -190,7 +228,7 @@ prepare (GeglOperation *operation)
     {
       props = g_new (NPDProperties, 1);
       props->first_run = TRUE;
-      o->chant_data = props;
+      o->chant_data    = props;
     }
   
   gegl_operation_set_format (operation, "input",
@@ -220,7 +258,9 @@ process (GeglOperation       *operation,
       NPDImage *input_image = g_new (NPDImage, 1);
       NPDDisplay *display = g_new (NPDDisplay, 1);
 
-      npd_init (npd_set_pixel_color_impl, npd_get_pixel_color_impl);
+      npd_init (npd_set_pixel_color_impl,
+                npd_get_pixel_color_impl,
+                npd_draw_line_impl);
 
       npd_create_image (input_image, input, format);
       width = input_image->width;
@@ -236,7 +276,6 @@ process (GeglOperation       *operation,
       npd_create_list_of_overlapping_points (hm);
 
       model->display = display;
-
       o->model = model;
 
       memcpy (output_buffer, input_image->buffer, length);
@@ -246,6 +285,7 @@ process (GeglOperation       *operation,
   else
     {
       npd_set_deformation_type (model, o->ASAP_deformation, o->MLS_weights);
+      model->mesh_visible = o->mesh_visible;
 
       output_buffer = model->display->image.buffer;
       memset (output_buffer, 0, length);
@@ -273,8 +313,7 @@ gegl_chant_class_init (GeglChantClass *klass)
   gegl_operation_class_set_keys (operation_class,
     "categories"  , "transform",
     "name"        , "gegl:npd",
-/*    "description" , _("Performs n-point image deformation"),*/
-    "description" , "Performs n-point image deformation",
+    "description" , _("Performs n-point image deformation"),
     NULL);
 }