Fix T60778: Grease pencil Hook modifieronly affects strokes with more than 2 points

Also fixed Lattice and Noise modifier.

3 files changed, 25 insertions, 12 deletions

diff --git a/source/blender/gpencil_modifiers/intern/MOD_gpencilhook.c b/source/blender/gpencil_modifiers/intern/MOD_gpencilhook.c
index 97f260f307f..06cdbfcbbce 100644
--- a/source/blender/gpencil_modifiers/intern/MOD_gpencilhook.c
+++ b/source/blender/gpencil_modifiers/intern/MOD_gpencilhook.c
@@ -210,7 +210,7 @@ static void deformStroke(
 
 	if (!is_stroke_affected_by_modifier(
 	            ob,
-	            mmd->layername, mmd->pass_index, mmd->layer_pass, 3, gpl, gps,
+	            mmd->layername, mmd->pass_index, mmd->layer_pass, 1, gpl, gps,
 	            mmd->flag & GP_HOOK_INVERT_LAYER, mmd->flag & GP_HOOK_INVERT_PASS,
 	            mmd->flag & GP_HOOK_INVERT_LAYERPASS))
 	{
diff --git a/source/blender/gpencil_modifiers/intern/MOD_gpencillattice.c b/source/blender/gpencil_modifiers/intern/MOD_gpencillattice.c
index 1d8f2c20b59..c938446a623 100644
--- a/source/blender/gpencil_modifiers/intern/MOD_gpencillattice.c
+++ b/source/blender/gpencil_modifiers/intern/MOD_gpencillattice.c
@@ -83,7 +83,7 @@ static void deformStroke(
 
 	if (!is_stroke_affected_by_modifier(
 	            ob,
-	            mmd->layername, mmd->pass_index, mmd->layer_pass, 3, gpl, gps,
+	            mmd->layername, mmd->pass_index, mmd->layer_pass, 1, gpl, gps,
 	            mmd->flag & GP_LATTICE_INVERT_LAYER, mmd->flag & GP_LATTICE_INVERT_PASS,
 	            mmd->flag & GP_LATTICE_INVERT_LAYERPASS))
 	{
diff --git a/source/blender/gpencil_modifiers/intern/MOD_gpencilnoise.c b/source/blender/gpencil_modifiers/intern/MOD_gpencilnoise.c
index e25908d2d01..94f83f10fb5 100644
--- a/source/blender/gpencil_modifiers/intern/MOD_gpencilnoise.c
+++ b/source/blender/gpencil_modifiers/intern/MOD_gpencilnoise.c
@@ -96,8 +96,8 @@ static bool dependsOnTime(GpencilModifierData *md)
 
 /* aply noise effect based on stroke direction */
 static void deformStroke(
-        GpencilModifierData *md, Depsgraph *depsgraph,
-        Object *ob, bGPDlayer *gpl, bGPDstroke *gps)
+	GpencilModifierData *md, Depsgraph *depsgraph,
+	Object *ob, bGPDlayer *gpl, bGPDstroke *gps)
 {
 	NoiseGpencilModifierData *mmd = (NoiseGpencilModifierData *)md;
 	bGPDspoint *pt0, *pt1;
@@ -108,6 +108,7 @@ static void deformStroke(
 	int sc_frame = 0;
 	int sc_diff = 0;
 	const int def_nr = defgroup_name_index(ob, mmd->vgname);
+	const float unit_v3[3] = { 1.0f, 1.0f, 1.0f };
 
 	/* Random generator, only init once. */
 	if (mmd->rng == NULL) {
@@ -117,10 +118,10 @@ static void deformStroke(
 	}
 
 	if (!is_stroke_affected_by_modifier(
-	            ob,
-	            mmd->layername, mmd->pass_index, mmd->layer_pass, 3, gpl, gps,
-	            mmd->flag & GP_NOISE_INVERT_LAYER, mmd->flag & GP_NOISE_INVERT_PASS,
-	            mmd->flag & GP_NOISE_INVERT_LAYERPASS))
+		ob,
+		mmd->layername, mmd->pass_index, mmd->layer_pass, 1, gpl, gps,
+		mmd->flag & GP_NOISE_INVERT_LAYER, mmd->flag & GP_NOISE_INVERT_PASS,
+		mmd->flag & GP_NOISE_INVERT_LAYERPASS))
 	{
 		return;
 	}
@@ -130,7 +131,12 @@ static void deformStroke(
 	zero_v3(vec2);
 
 	/* calculate stroke normal*/
-	BKE_gpencil_stroke_normal(gps, normal);
+	if (gps->totpoints > 2) {
+		BKE_gpencil_stroke_normal(gps, normal);
+	}
+	else {
+		copy_v3_v3(normal, unit_v3);
+	}
 
 	/* move points */
 	for (int i = 0; i < gps->totpoints; i++) {
@@ -143,7 +149,7 @@ static void deformStroke(
 			if (gps->dvert) {
 				dvert = &gps->dvert[0];
 			}
-			pt0 = &gps->points[1];
+			pt0 = (gps->totpoints > 1) ? &gps->points[1] : &gps->points[0];
 			pt1 = &gps->points[0];
 		}
 		else {
@@ -174,7 +180,7 @@ static void deformStroke(
 			sc_diff = abs(mmd->scene_frame - sc_frame);
 			/* only recalc if the gp frame change or the number of scene frames is bigger than step */
 			if ((!gpl->actframe) || (mmd->gp_frame != gpl->actframe->framenum) ||
-			    (sc_diff >= mmd->step))
+				(sc_diff >= mmd->step))
 			{
 				vran = mmd->vrand1 = BLI_rng_get_float(mmd->rng);
 				vdir = mmd->vrand2 = BLI_rng_get_float(mmd->rng);
@@ -203,7 +209,14 @@ static void deformStroke(
 			mmd->gp_frame = -999999;
 		}
 
-		/* apply randomness to location of the point */
+		/* if vec2 is zero, set to something */
+		if (gps->totpoints < 3) {
+			if ((vec2[0] == 0.0f) && (vec2[1] == 0.0f) && (vec2[2] == 0.0f)) {
+				copy_v3_v3(vec2, unit_v3);
+			}
+		}
+
+			/* apply randomness to location of the point */
 		if (mmd->flag & GP_NOISE_MOD_LOCATION) {
 			/* factor is too sensitive, so need divide */
 			shift = ((vran * mmd->factor) / 1000.0f) * weight;