[Bf-blender-cvs] [ced987b] GPencil_Editing_Stage3: GPencil Eraser: Eraser is now pressure sensitive
Joshua Leung
noreply at git.blender.org
Sat Dec 12 15:24:09 CET 2015
Commit: ced987b5b4fee71daf8e08f7e742c165cb661f57
Author: Joshua Leung
Date: Sun Dec 13 03:23:37 2015 +1300
Branches: GPencil_Editing_Stage3
https://developer.blender.org/rBced987b5b4fee71daf8e08f7e742c165cb661f57
GPencil Eraser: Eraser is now pressure sensitive
Instead of immediately erasing points, the eraser now first reduces the thickness
of the stroke points before culling the ones that have become overly thin (and
cannot be rendered properly anyway as a result). It is also pressure sensitive now,
and has a linear falloff effect (i.e. points further away from the center of the
eraser circle get affected less). This should make it easier to use to eraser to
make fine adjustments to your sketches.
Notes:
* The eraser has been rewritten to use a new algorithm. Specifically, it now takes
advantage of the stroke point deletion methods developed for the Delete operator
instead of it's own buggy split-and-delete methods (which were only removing
a single point from each stroke each time).
* In tests so far, it seems to allow a wider range of control over what gets erased
and what doesn't. Pressing hard (or using a mouse) should still just erase everything
with relative ease still.
* The way that this behaves could still do with some tweaking. In particular, care
is needed when trying to use the eraser to "lighten up" tips of thin bunches of
strokes (e.g. eyebrows/moustaches), as it still tends to gobble these up too much.
We could probably do with some tool settings to control the eraser strength.
===================================================================
M source/blender/editors/gpencil/gpencil_intern.h
M source/blender/editors/gpencil/gpencil_paint.c
M source/blender/makesdna/DNA_gpencil_types.h
===================================================================
diff --git a/source/blender/editors/gpencil/gpencil_intern.h b/source/blender/editors/gpencil/gpencil_intern.h
index 4032e43..d9a6441 100644
--- a/source/blender/editors/gpencil/gpencil_intern.h
+++ b/source/blender/editors/gpencil/gpencil_intern.h
@@ -122,6 +122,10 @@ int gp_active_layer_poll(struct bContext *C);
extern ListBase gp_strokes_copypastebuf;
+/* Stroke Editing ------------------------------------ */
+
+void gp_stroke_delete_tagged_points(bGPDframe *gpf, bGPDstroke *gps, bGPDstroke *next_stroke, int tag_flags);
+
/* Layers Enums -------------------------------------- */
struct EnumPropertyItem *ED_gpencil_layers_enum_itemf(struct bContext *C, struct PointerRNA *ptr, struct PropertyRNA *prop, bool *r_free);
diff --git a/source/blender/editors/gpencil/gpencil_paint.c b/source/blender/editors/gpencil/gpencil_paint.c
index 16c16e2..620eadf 100644
--- a/source/blender/editors/gpencil/gpencil_paint.c
+++ b/source/blender/editors/gpencil/gpencil_paint.c
@@ -741,6 +741,7 @@ static void gp_stroke_newfrombuffer(tGPsdata *p)
/* --- 'Eraser' for 'Paint' Tool ------ */
+#if 0
/* eraser tool - remove segment from stroke/split stroke (after lasso inside) */
static bool gp_stroke_eraser_splitdel(bGPDframe *gpf, bGPDstroke *gps, int i)
{
@@ -846,6 +847,7 @@ static bool gp_stroke_eraser_splitdel(bGPDframe *gpf, bGPDstroke *gps, int i)
return true;
}
}
+#endif
/* which which point is infront (result should only be used for comparison) */
static float view3d_point_depth(const RegionView3D *rv3d, const float co[3])
@@ -858,6 +860,7 @@ static float view3d_point_depth(const RegionView3D *rv3d, const float co[3])
}
}
+/* only erase stroke points that are visible */
static bool gp_stroke_eraser_is_occluded(tGPsdata *p, const bGPDspoint *pt, const int x, const int y)
{
if ((p->sa->spacetype == SPACE_VIEW3D) &&
@@ -879,13 +882,29 @@ static bool gp_stroke_eraser_is_occluded(tGPsdata *p, const bGPDspoint *pt, cons
return false;
}
+/* apply a falloff effect to brush strength, based on distance */
+static float gp_stroke_eraser_calc_influence(tGPsdata *p, const int mval[2], const int radius, const int co[2])
+{
+ /* Linear Falloff... */
+ float distance = (float)len_v2v2_int(mval, co);
+ float fac;
+
+ CLAMP(distance, 0.0f, (float)radius);
+ fac = 1.0f - (distance / (float)radius);
+
+ /* Control this further using pen pressure */
+ fac *= p->pressure;
+
+ /* Return influence factor computed here */
+ return fac;
+}
/* eraser tool - evaluation per stroke */
/* TODO: this could really do with some optimization (KD-Tree/BVH?) */
static void gp_stroke_eraser_dostroke(tGPsdata *p,
+ bGPDlayer *gpl, bGPDframe *gpf, bGPDstroke *gps,
const int mval[2], const int mvalo[2],
- const int radius, const rcti *rect,
- bGPDframe *gpf, bGPDstroke *gps)
+ const int radius, const rcti *rect)
{
bGPDspoint *pt1, *pt2;
int pc1[2] = {0};
@@ -906,14 +925,40 @@ static void gp_stroke_eraser_dostroke(tGPsdata *p,
/* only check if point is inside */
if (len_v2v2_int(mval, pc1) <= radius) {
/* free stroke */
+ // XXX: pressure sensitive eraser should apply here too?
MEM_freeN(gps->points);
BLI_freelinkN(&gpf->strokes, gps);
}
}
}
else {
- /* loop over the points in the stroke, checking for intersections
- * - an intersection will require the stroke to be split
+ /* Pressure threshold at which stroke should be culled: Calculated as pressure value
+ * below which we would have invisible strokes
+ */
+ const float cull_thresh = (gpl->thickness) ? 1.0f / ((float)gpl->thickness) : 1.0f;
+
+ /* Amount to decrease the pressure of each point with each stroke */
+ // TODO: Fetch from toolsettings, or compute based on thickness instead?
+ const float strength = 0.1f;
+
+ /* Perform culling? */
+ bool do_cull = false;
+
+
+ /* Clear Tags
+ *
+ * Note: It's better this way, as we are sure that
+ * we don't miss anything, though things will be
+ * slightly slower as a result
+ */
+ for (i = 0; i < gps->totpoints; i++) {
+ bGPDspoint *pt = &gps->points[i];
+ pt->flag &= ~GP_SPOINT_TAG;
+ }
+
+ /* First Pass: Loop over the points in the stroke
+ * 1) Thin out parts of the stroke under the brush
+ * 2) Tag "too thin" parts for removal (in second pass)
*/
for (i = 0; (i + 1) < gps->totpoints; i++) {
/* get points to work with */
@@ -923,11 +968,11 @@ static void gp_stroke_eraser_dostroke(tGPsdata *p,
gp_point_to_xy(&p->gsc, gps, pt1, &pc1[0], &pc1[1]);
gp_point_to_xy(&p->gsc, gps, pt2, &pc2[0], &pc2[1]);
- /* check that point segment of the boundbox of the eraser stroke */
+ /* Check that point segment of the boundbox of the eraser stroke */
if (((!ELEM(V2D_IS_CLIPPED, pc1[0], pc1[1])) && BLI_rcti_isect_pt(rect, pc1[0], pc1[1])) ||
((!ELEM(V2D_IS_CLIPPED, pc2[0], pc2[1])) && BLI_rcti_isect_pt(rect, pc2[0], pc2[1])))
{
- /* check if point segment of stroke had anything to do with
+ /* Check if point segment of stroke had anything to do with
* eraser region (either within stroke painted, or on its lines)
* - this assumes that linewidth is irrelevant
*/
@@ -935,13 +980,32 @@ static void gp_stroke_eraser_dostroke(tGPsdata *p,
if ((gp_stroke_eraser_is_occluded(p, pt1, pc1[0], pc1[1]) == false) ||
(gp_stroke_eraser_is_occluded(p, pt2, pc2[0], pc2[1]) == false))
{
- /* if function returns true, break this loop (as no more point to check) */
- if (gp_stroke_eraser_splitdel(gpf, gps, i))
- break;
+ /* Point is affected: */
+ /* 1) Adjust thickness
+ * - Influence of eraser falls off with distance from the middle of the eraser
+ * - Second point gets less influence, as it might get hit again in the next segment
+ */
+ pt1->pressure -= gp_stroke_eraser_calc_influence(p, mval, radius, pc1) * strength;
+ pt2->pressure -= gp_stroke_eraser_calc_influence(p, mval, radius, pc2) * strength / 2.0f;
+
+ /* 2) Tag any point with overly low influence for removal in the next pass */
+ if (pt1->pressure < cull_thresh) {
+ pt1->flag |= GP_SPOINT_TAG;
+ do_cull = true;
+ }
+ if (pt2->pressure < cull_thresh) {
+ pt2->flag |= GP_SPOINT_TAG;
+ do_cull = true;
+ }
}
}
}
}
+
+ /* Second Pass: Remove any points that are tagged */
+ if (do_cull) {
+ gp_stroke_delete_tagged_points(gpf, gps, gps->next, GP_SPOINT_TAG);
+ }
}
}
@@ -990,7 +1054,7 @@ static void gp_stroke_doeraser(tGPsdata *p)
* (e.g. 2D space strokes in the 3D view, if the same datablock is shared)
*/
if (ED_gpencil_stroke_can_use_direct(p->sa, gps)) {
- gp_stroke_eraser_dostroke(p, p->mval, p->mvalo, p->radius, &rect, gpf, gps);
+ gp_stroke_eraser_dostroke(p, gpl, gpf, gps, p->mval, p->mvalo, p->radius, &rect);
}
}
}
diff --git a/source/blender/makesdna/DNA_gpencil_types.h b/source/blender/makesdna/DNA_gpencil_types.h
index be4cfbe..aa98ddb 100644
--- a/source/blender/makesdna/DNA_gpencil_types.h
+++ b/source/blender/makesdna/DNA_gpencil_types.h
@@ -51,7 +51,10 @@ typedef struct bGPDspoint {
/* bGPDspoint->flag */
typedef enum eGPDspoint_Flag {
/* stroke point is selected (for editing) */
- GP_SPOINT_SELECT = (1 << 0)
+ GP_SPOINT_SELECT = (1 << 0),
+
+ /* stroke point is tagged (for some editing operation) */
+ GP_SPOINT_TAG = (1 << 1),
} eGPSPoint_Flag;
/* Grease-Pencil Annotations - 'Stroke'
More information about the Bf-blender-cvs
mailing list