1 /* GIMP - The GNU Image Manipulation Program
2  * Copyright (C) 1995 Spencer Kimball and Peter Mattis
3  *
4  * This program is free software: you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; either version 3 of the License, or
7  * (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
16  */
17 
18 #include "config.h"
19 
20 #include <string.h>
21 
22 #include <cairo.h>
23 #include <gdk-pixbuf/gdk-pixbuf.h>
24 #include <gegl.h>
25 
26 #include <mypaint-brush.h>
27 
28 #include "libgimpmath/gimpmath.h"
29 #include "libgimpcolor/gimpcolor.h"
30 
31 #include "paint-types.h"
32 
33 #include "gegl/gimp-gegl-utils.h"
34 
35 #include "core/gimp.h"
36 #include "core/gimp-palettes.h"
37 #include "core/gimpdrawable.h"
38 #include "core/gimperror.h"
39 #include "core/gimpmybrush.h"
40 #include "core/gimppickable.h"
41 #include "core/gimpsymmetry.h"
42 
43 #include "gimpmybrushcore.h"
44 #include "gimpmybrushsurface.h"
45 #include "gimpmybrushoptions.h"
46 
47 #include "gimp-intl.h"
48 
49 
50 struct _GimpMybrushCorePrivate
51 {
52   GimpMybrush        *mybrush;
53   GimpMybrushSurface *surface;
54   GList              *brushes;
55   gboolean            synthetic;
56   gint64              last_time;
57 };
58 
59 
60 /*  local function prototypes  */
61 
62 static void      gimp_mybrush_core_finalize       (GObject           *object);
63 
64 static gboolean  gimp_mybrush_core_start          (GimpPaintCore     *paint_core,
65                                                    GimpDrawable      *drawable,
66                                                    GimpPaintOptions  *paint_options,
67                                                    const GimpCoords  *coords,
68                                                    GError           **error);
69 static void      gimp_mybrush_core_interpolate    (GimpPaintCore     *paint_core,
70                                                    GimpDrawable      *drawable,
71                                                    GimpPaintOptions  *paint_options,
72                                                    guint32            time);
73 static void      gimp_mybrush_core_paint          (GimpPaintCore     *paint_core,
74                                                    GimpDrawable      *drawable,
75                                                    GimpPaintOptions  *paint_options,
76                                                    GimpSymmetry      *sym,
77                                                    GimpPaintState     paint_state,
78                                                    guint32            time);
79 static void      gimp_mybrush_core_motion         (GimpPaintCore     *paint_core,
80                                                    GimpDrawable      *drawable,
81                                                    GimpPaintOptions  *paint_options,
82                                                    GimpSymmetry      *sym,
83                                                    guint32            time);
84 static void      gimp_mybrush_core_create_brushes (GimpMybrushCore   *mybrush,
85                                                    GimpDrawable      *drawable,
86                                                    GimpPaintOptions  *paint_options,
87                                                    GimpSymmetry      *sym);
88 
89 
G_DEFINE_TYPE_WITH_PRIVATE(GimpMybrushCore,gimp_mybrush_core,GIMP_TYPE_PAINT_CORE)90 G_DEFINE_TYPE_WITH_PRIVATE (GimpMybrushCore, gimp_mybrush_core,
91                             GIMP_TYPE_PAINT_CORE)
92 
93 #define parent_class gimp_mybrush_core_parent_class
94 
95 
96 void
97 gimp_mybrush_core_register (Gimp                      *gimp,
98                             GimpPaintRegisterCallback  callback)
99 {
100   (* callback) (gimp,
101                 GIMP_TYPE_MYBRUSH_CORE,
102                 GIMP_TYPE_MYBRUSH_OPTIONS,
103                 "gimp-mybrush",
104                 _("Mybrush"),
105                 "gimp-tool-mypaint-brush");
106 }
107 
108 static void
gimp_mybrush_core_class_init(GimpMybrushCoreClass * klass)109 gimp_mybrush_core_class_init (GimpMybrushCoreClass *klass)
110 {
111   GObjectClass       *object_class     = G_OBJECT_CLASS (klass);
112   GimpPaintCoreClass *paint_core_class = GIMP_PAINT_CORE_CLASS (klass);
113 
114   object_class->finalize        = gimp_mybrush_core_finalize;
115 
116   paint_core_class->start       = gimp_mybrush_core_start;
117   paint_core_class->paint       = gimp_mybrush_core_paint;
118   paint_core_class->interpolate = gimp_mybrush_core_interpolate;
119 }
120 
121 static void
gimp_mybrush_core_init(GimpMybrushCore * mybrush)122 gimp_mybrush_core_init (GimpMybrushCore *mybrush)
123 {
124   mybrush->private = gimp_mybrush_core_get_instance_private (mybrush);
125 }
126 
127 static void
gimp_mybrush_core_finalize(GObject * object)128 gimp_mybrush_core_finalize (GObject *object)
129 {
130   GimpMybrushCore *core = GIMP_MYBRUSH_CORE (object);
131 
132   if (core->private->brushes)
133     {
134       g_list_free_full (core->private->brushes,
135                         (GDestroyNotify) mypaint_brush_unref);
136       core->private->brushes = NULL;
137     }
138 
139   G_OBJECT_CLASS (parent_class)->finalize (object);
140 }
141 
142 static gboolean
gimp_mybrush_core_start(GimpPaintCore * paint_core,GimpDrawable * drawable,GimpPaintOptions * paint_options,const GimpCoords * coords,GError ** error)143 gimp_mybrush_core_start (GimpPaintCore     *paint_core,
144                          GimpDrawable      *drawable,
145                          GimpPaintOptions  *paint_options,
146                          const GimpCoords  *coords,
147                          GError           **error)
148 {
149   GimpMybrushCore *core    = GIMP_MYBRUSH_CORE (paint_core);
150   GimpContext     *context = GIMP_CONTEXT (paint_options);
151 
152   core->private->mybrush = gimp_context_get_mybrush (context);
153 
154   if (! core->private->mybrush)
155     {
156       g_set_error_literal (error, GIMP_ERROR, GIMP_FAILED,
157                            _("No MyPaint brushes available for use with this tool."));
158       return FALSE;
159     }
160 
161   return TRUE;
162 }
163 
164 static void
gimp_mybrush_core_interpolate(GimpPaintCore * paint_core,GimpDrawable * drawable,GimpPaintOptions * paint_options,guint32 time)165 gimp_mybrush_core_interpolate (GimpPaintCore    *paint_core,
166                                GimpDrawable     *drawable,
167                                GimpPaintOptions *paint_options,
168                                guint32           time)
169 {
170   GimpMybrushCore *mybrush = GIMP_MYBRUSH_CORE (paint_core);
171 
172   /* If this is the first motion the brush has received then
173    * we're being asked to draw a synthetic stroke in line mode
174    */
175   if (mybrush->private->last_time < 0)
176     {
177       GimpCoords saved_coords = paint_core->cur_coords;
178 
179       paint_core->cur_coords = paint_core->last_coords;
180 
181       mybrush->private->synthetic = TRUE;
182 
183       gimp_paint_core_paint (paint_core, drawable, paint_options,
184                              GIMP_PAINT_STATE_MOTION, time);
185 
186       paint_core->cur_coords = saved_coords;
187     }
188 
189   gimp_paint_core_paint (paint_core, drawable, paint_options,
190                          GIMP_PAINT_STATE_MOTION, time);
191 
192   paint_core->last_coords = paint_core->cur_coords;
193 }
194 
195 static void
gimp_mybrush_core_paint(GimpPaintCore * paint_core,GimpDrawable * drawable,GimpPaintOptions * paint_options,GimpSymmetry * sym,GimpPaintState paint_state,guint32 time)196 gimp_mybrush_core_paint (GimpPaintCore    *paint_core,
197                          GimpDrawable     *drawable,
198                          GimpPaintOptions *paint_options,
199                          GimpSymmetry     *sym,
200                          GimpPaintState    paint_state,
201                          guint32           time)
202 {
203   GimpMybrushCore *mybrush = GIMP_MYBRUSH_CORE (paint_core);
204   GimpContext     *context = GIMP_CONTEXT (paint_options);
205   GimpRGB          fg;
206 
207   switch (paint_state)
208     {
209     case GIMP_PAINT_STATE_INIT:
210       gimp_context_get_foreground (context, &fg);
211       gimp_palettes_add_color_history (context->gimp, &fg);
212       gimp_symmetry_set_stateful (sym, TRUE);
213 
214       mybrush->private->surface =
215         gimp_mypaint_surface_new (gimp_drawable_get_buffer (drawable),
216                                   gimp_drawable_get_active_mask (drawable),
217                                   paint_core->mask_buffer,
218                                   paint_core->mask_x_offset,
219                                   paint_core->mask_y_offset,
220                                   GIMP_MYBRUSH_OPTIONS (paint_options));
221 
222       gimp_mybrush_core_create_brushes (mybrush, drawable, paint_options, sym);
223 
224       mybrush->private->last_time = -1;
225       mybrush->private->synthetic = FALSE;
226       break;
227 
228     case GIMP_PAINT_STATE_MOTION:
229       gimp_mybrush_core_motion (paint_core, drawable, paint_options,
230                                 sym, time);
231       break;
232 
233     case GIMP_PAINT_STATE_FINISH:
234       gimp_symmetry_set_stateful (sym, FALSE);
235       mypaint_surface_unref ((MyPaintSurface *) mybrush->private->surface);
236       mybrush->private->surface = NULL;
237 
238       g_list_free_full (mybrush->private->brushes,
239                         (GDestroyNotify) mypaint_brush_unref);
240       mybrush->private->brushes = NULL;
241       break;
242     }
243 }
244 
245 static void
gimp_mybrush_core_motion(GimpPaintCore * paint_core,GimpDrawable * drawable,GimpPaintOptions * paint_options,GimpSymmetry * sym,guint32 time)246 gimp_mybrush_core_motion (GimpPaintCore    *paint_core,
247                           GimpDrawable     *drawable,
248                           GimpPaintOptions *paint_options,
249                           GimpSymmetry     *sym,
250                           guint32           time)
251 {
252   GimpMybrushCore  *mybrush = GIMP_MYBRUSH_CORE (paint_core);
253   MyPaintRectangle  rect;
254   GList            *iter;
255   gdouble           dt = 0.0;
256   gint              n_strokes;
257   gint              i;
258 
259   n_strokes = gimp_symmetry_get_size (sym);
260 
261   /* The number of strokes may change during a motion, depending on
262    * the type of symmetry. When that happens, reset the brushes.
263    */
264   if (g_list_length (mybrush->private->brushes) != n_strokes)
265     {
266       gimp_mybrush_core_create_brushes (mybrush, drawable, paint_options, sym);
267     }
268 
269   mypaint_surface_begin_atomic ((MyPaintSurface *) mybrush->private->surface);
270 
271   if (mybrush->private->last_time < 0)
272     {
273       /* First motion, so we need zero pressure events to start the strokes */
274       for (iter = mybrush->private->brushes, i = 0;
275            iter;
276            iter = g_list_next (iter), i++)
277         {
278           MyPaintBrush *brush  = iter->data;
279           GimpCoords   *coords = gimp_symmetry_get_coords (sym, i);
280 
281           mypaint_brush_stroke_to (brush,
282                                    (MyPaintSurface *) mybrush->private->surface,
283                                    coords->x,
284                                    coords->y,
285                                    0.0f,
286                                    coords->xtilt,
287                                    coords->ytilt,
288                                    1.0f /* Pretend the cursor hasn't moved in a while */);
289         }
290 
291       dt = 0.015;
292     }
293   else if (mybrush->private->synthetic)
294     {
295       GimpVector2 v = { paint_core->cur_coords.x - paint_core->last_coords.x,
296                         paint_core->cur_coords.y - paint_core->last_coords.y };
297 
298       dt = 0.0005 * gimp_vector2_length_val (v);
299     }
300   else
301     {
302       dt = (time - mybrush->private->last_time) * 0.001;
303     }
304 
305   for (iter = mybrush->private->brushes, i = 0;
306        iter;
307        iter = g_list_next (iter), i++)
308     {
309       MyPaintBrush *brush    = iter->data;
310       GimpCoords   *coords   = gimp_symmetry_get_coords (sym, i);
311       gdouble       pressure = coords->pressure;
312 
313       /* libmypaint expects non-extended devices to default to 0.5 pressure */
314       if (! coords->extended)
315         pressure = 0.5f;
316 
317       mypaint_brush_stroke_to (brush,
318                                (MyPaintSurface *) mybrush->private->surface,
319                                coords->x,
320                                coords->y,
321                                pressure,
322                                coords->xtilt,
323                                coords->ytilt,
324                                dt);
325     }
326 
327   mybrush->private->last_time = time;
328 
329   mypaint_surface_end_atomic ((MyPaintSurface *) mybrush->private->surface,
330                               &rect);
331 
332   if (rect.width > 0 && rect.height > 0)
333     {
334       paint_core->x1 = MIN (paint_core->x1, rect.x);
335       paint_core->y1 = MIN (paint_core->y1, rect.y);
336       paint_core->x2 = MAX (paint_core->x2, rect.x + rect.width);
337       paint_core->y2 = MAX (paint_core->y2, rect.y + rect.height);
338 
339       gimp_drawable_update (drawable, rect.x, rect.y, rect.width, rect.height);
340     }
341 }
342 
343 static void
gimp_mybrush_core_create_brushes(GimpMybrushCore * mybrush,GimpDrawable * drawable,GimpPaintOptions * paint_options,GimpSymmetry * sym)344 gimp_mybrush_core_create_brushes (GimpMybrushCore  *mybrush,
345                                   GimpDrawable     *drawable,
346                                   GimpPaintOptions *paint_options,
347                                   GimpSymmetry     *sym)
348 {
349   GimpMybrushOptions *options = GIMP_MYBRUSH_OPTIONS (paint_options);
350   GimpContext        *context = GIMP_CONTEXT (paint_options);
351   GimpRGB             fg;
352   GimpHSV             hsv;
353   gint                n_strokes;
354   gint                i;
355 
356   if (mybrush->private->brushes)
357     {
358       g_list_free_full (mybrush->private->brushes,
359                         (GDestroyNotify) mypaint_brush_unref);
360       mybrush->private->brushes = NULL;
361     }
362 
363   if (options->eraser)
364     gimp_context_get_background (context, &fg);
365   else
366     gimp_context_get_foreground (context, &fg);
367 
368   gimp_pickable_srgb_to_image_color (GIMP_PICKABLE (drawable),
369                                      &fg, &fg);
370   gimp_rgb_to_hsv (&fg, &hsv);
371 
372   n_strokes = gimp_symmetry_get_size (sym);
373 
374   for (i = 0; i < n_strokes; i++)
375     {
376       MyPaintBrush *brush = mypaint_brush_new ();
377       const gchar  *brush_data;
378 
379       mypaint_brush_from_defaults (brush);
380       brush_data = gimp_mybrush_get_brush_json (mybrush->private->mybrush);
381       if (brush_data)
382         mypaint_brush_from_string (brush, brush_data);
383 
384       if (! mypaint_brush_get_base_value (brush,
385                                           MYPAINT_BRUSH_SETTING_RESTORE_COLOR))
386         {
387           mypaint_brush_set_base_value (brush,
388                                         MYPAINT_BRUSH_SETTING_COLOR_H,
389                                         hsv.h);
390           mypaint_brush_set_base_value (brush,
391                                         MYPAINT_BRUSH_SETTING_COLOR_S,
392                                         hsv.s);
393           mypaint_brush_set_base_value (brush,
394                                         MYPAINT_BRUSH_SETTING_COLOR_V,
395                                         hsv.v);
396         }
397 
398       mypaint_brush_set_base_value (brush,
399                                     MYPAINT_BRUSH_SETTING_RADIUS_LOGARITHMIC,
400                                     options->radius);
401       mypaint_brush_set_base_value (brush,
402                                     MYPAINT_BRUSH_SETTING_OPAQUE,
403                                     options->opaque *
404                                     gimp_context_get_opacity (context));
405       mypaint_brush_set_base_value (brush,
406                                     MYPAINT_BRUSH_SETTING_HARDNESS,
407                                     options->hardness);
408       mypaint_brush_set_base_value (brush,
409                                     MYPAINT_BRUSH_SETTING_ERASER,
410                                     (options->eraser &&
411                                      gimp_drawable_has_alpha (drawable)) ?
412                                     1.0f : 0.0f);
413 
414       mypaint_brush_new_stroke (brush);
415 
416       mybrush->private->brushes = g_list_prepend (mybrush->private->brushes,
417                                                   brush);
418     }
419 
420   mybrush->private->brushes = g_list_reverse (mybrush->private->brushes);
421 }
422