Debug drawing for simulations, to aid in visualizing abstract data such

as forces, velocities, contact points etc.

This uses a hash table to store debug elements (dots, lines, vectors at
this point). The hash table allows continuous display of elements that
are generated only in certain time steps, e.g. contact points, while
avoiding massive memory allocation. In any case, this system is really
a development feature, but very helpful in finding issues with the
internal solver data.

4 files changed, 151 insertions, 0 deletions

diff --git a/source/blender/editors/space_view3d/CMakeLists.txt b/source/blender/editors/space_view3d/CMakeLists.txt
index 320267a4a7c..ab69e67361d 100644
--- a/source/blender/editors/space_view3d/CMakeLists.txt
+++ b/source/blender/editors/space_view3d/CMakeLists.txt
@@ -44,6 +44,7 @@ set(SRC
 	drawarmature.c
 	drawmesh.c
 	drawobject.c
+	drawsimdebug.c
 	drawvolume.c
 	space_view3d.c
 	view3d_buttons.c
diff --git a/source/blender/editors/space_view3d/drawobject.c b/source/blender/editors/space_view3d/drawobject.c
index 55b621d5aba..e44012279b4 100644
--- a/source/blender/editors/space_view3d/drawobject.c
+++ b/source/blender/editors/space_view3d/drawobject.c
@@ -7488,6 +7488,12 @@ void draw_object(Scene *scene, ARegion *ar, View3D *v3d, Base *base, const short
 			}
 
 			draw_new_particle_system(scene, v3d, rv3d, base, psys, dt, dflag);
+
+			/* debug data */
+			if (psys->part->type == PART_HAIR) {
+				if (psys->clmd && psys->clmd->debug_data)
+					draw_sim_debug_data(scene, v3d, ar, base, psys->clmd->debug_data);
+			}
 		}
 		invert_m4_m4(ob->imat, ob->obmat);
 		view3d_cached_text_draw_end(v3d, ar, 0, NULL);
diff --git a/source/blender/editors/space_view3d/drawsimdebug.c b/source/blender/editors/space_view3d/drawsimdebug.c
new file mode 100644
index 00000000000..83fee946c99
--- /dev/null
+++ b/source/blender/editors/space_view3d/drawsimdebug.c
@@ -0,0 +1,140 @@
+/*
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version. 
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2014 by the Blender Foundation.
+ * All rights reserved.
+ *
+ * The Original Code is: all of this file.
+ *
+ * Contributor(s): Lukas Toenne
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file blender/editors/space_view3d/drawsimdebug.c
+ *  \ingroup spview3d
+ */
+
+#include "MEM_guardedalloc.h"
+
+#include "DNA_scene_types.h"
+#include "DNA_screen_types.h"
+#include "DNA_view3d_types.h"
+#include "DNA_object_types.h"
+
+#include "BLI_blenlib.h"
+#include "BLI_math.h"
+#include "BLI_utildefines.h"
+#include "BLI_ghash.h"
+
+#include "BKE_effect.h"
+#include "BKE_global.h"
+#include "BKE_modifier.h"
+
+#include "view3d_intern.h"
+
+#include "BIF_gl.h"
+#include "BIF_glutil.h"
+
+#include "UI_resources.h"
+
+static void draw_sim_debug_elements(SimDebugData *debug_data)
+{
+	GHashIterator iter;
+	
+	/**** dots ****/
+	
+	glPointSize(3.0f);
+	glBegin(GL_POINTS);
+	for (BLI_ghashIterator_init(&iter, debug_data->gh); !BLI_ghashIterator_done(&iter); BLI_ghashIterator_step(&iter)) {
+		SimDebugElement *elem = BLI_ghashIterator_getValue(&iter);
+		if (elem->type != SIM_DEBUG_ELEM_DOT)
+			continue;
+		
+		glColor3f(elem->color[0], elem->color[1], elem->color[2]);
+		glVertex3f(elem->v1[0], elem->v1[1], elem->v1[2]);
+	}
+	glEnd();
+	glPointSize(1.0f);
+	
+	/**** lines ****/
+	
+	glBegin(GL_LINES);
+	for (BLI_ghashIterator_init(&iter, debug_data->gh); !BLI_ghashIterator_done(&iter); BLI_ghashIterator_step(&iter)) {
+		SimDebugElement *elem = BLI_ghashIterator_getValue(&iter);
+		if (elem->type != SIM_DEBUG_ELEM_LINE)
+			continue;
+		
+		glColor3f(elem->color[0], elem->color[1], elem->color[2]);
+		glVertex3f(elem->v1[0], elem->v1[1], elem->v1[2]);
+		glVertex3f(elem->v2[0], elem->v2[1], elem->v2[2]);
+	}
+	glEnd();
+	
+	/**** vectors ****/
+	
+	glPointSize(2.0f);
+	glBegin(GL_POINTS);
+	for (BLI_ghashIterator_init(&iter, debug_data->gh); !BLI_ghashIterator_done(&iter); BLI_ghashIterator_step(&iter)) {
+		SimDebugElement *elem = BLI_ghashIterator_getValue(&iter);
+		if (elem->type != SIM_DEBUG_ELEM_VECTOR)
+			continue;
+		
+		glColor3f(elem->color[0], elem->color[1], elem->color[2]);
+		glVertex3f(elem->v1[0], elem->v1[1], elem->v1[2]);
+	}
+	glEnd();
+	glPointSize(1.0f);
+	
+	glBegin(GL_LINES);
+	for (BLI_ghashIterator_init(&iter, debug_data->gh); !BLI_ghashIterator_done(&iter); BLI_ghashIterator_step(&iter)) {
+		SimDebugElement *elem = BLI_ghashIterator_getValue(&iter);
+		float t[3];
+		if (elem->type != SIM_DEBUG_ELEM_VECTOR)
+			continue;
+		
+		glColor3f(elem->color[0], elem->color[1], elem->color[2]);
+		glVertex3f(elem->v1[0], elem->v1[1], elem->v1[2]);
+		add_v3_v3v3(t, elem->v1, elem->v2);
+		glVertex3f(t[0], t[1], t[2]);
+	}
+	glEnd();
+}
+
+void draw_sim_debug_data(Scene *UNUSED(scene), View3D *UNUSED(v3d), ARegion *ar, Base *UNUSED(base), SimDebugData *debug_data)
+{
+	RegionView3D *rv3d = ar->regiondata;
+	/*Object *ob = base->object;*/
+	/*float imat[4][4];*/
+	
+	/*invert_m4_m4(imat, rv3d->viewmatob);*/
+	
+//	glDepthMask(GL_FALSE);
+//	glEnable(GL_BLEND);
+	
+	glPushMatrix();
+	glLoadMatrixf(rv3d->viewmat);
+	
+	if (debug_data) {
+		draw_sim_debug_elements(debug_data);
+	}
+	
+	glPopMatrix();
+	
+//	glDepthMask(GL_TRUE);
+//	glDisable(GL_BLEND);
+}
diff --git a/source/blender/editors/space_view3d/view3d_intern.h b/source/blender/editors/space_view3d/view3d_intern.h
index d3a9f5ca967..c0517cf1151 100644
--- a/source/blender/editors/space_view3d/view3d_intern.h
+++ b/source/blender/editors/space_view3d/view3d_intern.h
@@ -48,6 +48,7 @@ struct bMotionPath;
 struct bPoseChannel;
 struct bScreen;
 struct Mesh;
+struct SimDebugData;
 struct wmNDOFMotionData;
 struct wmOperatorType;
 struct wmWindowManager;
@@ -177,6 +178,9 @@ void draw_mesh_paint_weight_edges(RegionView3D *rv3d, struct DerivedMesh *dm,
 void draw_mesh_paint(View3D *v3d, RegionView3D *rv3d,
                      struct Object *ob, struct DerivedMesh *dm, const int draw_flags);
 
+/* drawsimdebug.c */
+void draw_sim_debug_data(Scene *scene, View3D *v3d, ARegion *ar, Base *base, struct SimDebugData *debug_data);
+
 /* view3d_draw.c */
 void view3d_main_area_draw(const struct bContext *C, struct ARegion *ar);
 void ED_view3d_draw_depth(Scene *scene, struct ARegion *ar, View3D *v3d, bool alphaoverride);