LineArt: Camera Overscan

Expand camera effective region to a portion beyond image frame so strokes won't end right at the border.

Reviewed By: Antonio Vazquez (antoniov)

Differential Revision: https://developer.blender.org/D12049

3 files changed, 24 insertions, 9 deletions

diff --git a/source/blender/gpencil_modifiers/intern/MOD_gpencillineart.c b/source/blender/gpencil_modifiers/intern/MOD_gpencillineart.c
index 8228915c6a8..ac458041ca3 100644
--- a/source/blender/gpencil_modifiers/intern/MOD_gpencillineart.c
+++ b/source/blender/gpencil_modifiers/intern/MOD_gpencillineart.c
@@ -380,6 +380,8 @@ static void options_panel_draw(const bContext *UNUSED(C), Panel *panel)
     return;
   }
 
+  uiItemR(layout, ptr, "overscan", 0, NULL, ICON_NONE);
+
   uiLayout *col = uiLayoutColumn(layout, true);
 
   uiItemR(col, ptr, "use_remove_doubles", 0, NULL, ICON_NONE);
diff --git a/source/blender/gpencil_modifiers/intern/lineart/MOD_lineart.h b/source/blender/gpencil_modifiers/intern/lineart/MOD_lineart.h
index 3730dba8e70..8eed2e705e8 100644
--- a/source/blender/gpencil_modifiers/intern/lineart/MOD_lineart.h
+++ b/source/blender/gpencil_modifiers/intern/lineart/MOD_lineart.h
@@ -228,6 +228,8 @@ typedef struct LineartRenderBuffer {
   double view_projection[4][4];
   double view[4][4];
 
+  float overscan;
+
   struct LineartBoundingArea *initial_bounding_areas;
   unsigned int bounding_area_count;
 
diff --git a/source/blender/gpencil_modifiers/intern/lineart/lineart_cpu.c b/source/blender/gpencil_modifiers/intern/lineart/lineart_cpu.c
index a97d79a886e..3a6d6a8f32f 100644
--- a/source/blender/gpencil_modifiers/intern/lineart/lineart_cpu.c
+++ b/source/blender/gpencil_modifiers/intern/lineart/lineart_cpu.c
@@ -2013,7 +2013,10 @@ static void lineart_geometry_load_assign_thread(LineartObjectLoadTaskInfo *olti_
   use_olti->pending = obi;
 }
 
-static bool lineart_geometry_check_visible(double (*model_view_proj)[4], Object *use_ob)
+static bool lineart_geometry_check_visible(double (*model_view_proj)[4],
+                                           double shift_x,
+                                           double shift_y,
+                                           Object *use_ob)
 {
   BoundBox *bb = BKE_object_boundbox_get(use_ob);
   if (!bb) {
@@ -2027,6 +2030,8 @@ static bool lineart_geometry_check_visible(double (*model_view_proj)[4], Object
     copy_v3db_v3fl(co[i], bb->vec[i]);
     copy_v3_v3_db(tmp, co[i]);
     mul_v4_m4v3_db(co[i], model_view_proj, tmp);
+    co[i][0] -= shift_x * 2 * co[i][3];
+    co[i][1] -= shift_y * 2 * co[i][3];
   }
 
   bool cond[6] = {true, true, true, true, true, true};
@@ -2062,11 +2067,6 @@ static void lineart_main_load_geometries(
   int fit = BKE_camera_sensor_fit(cam->sensor_fit, rb->w, rb->h);
   double asp = ((double)rb->w / (double)rb->h);
 
-  double t_start;
-
-  if (G.debug_value == 4000) {
-    t_start = PIL_check_seconds_timer();
-  }
   int bound_box_discard_count = 0;
 
   if (cam->type == CAM_PERSP) {
@@ -2076,14 +2076,20 @@ static void lineart_main_load_geometries(
     if (fit == CAMERA_SENSOR_FIT_HOR && asp < 1) {
       sensor /= asp;
     }
-    double fov = focallength_to_fov(cam->lens, sensor);
+    const double fov = focallength_to_fov(cam->lens / (1 + rb->overscan), sensor);
     lineart_matrix_perspective_44d(proj, fov, asp, cam->clip_start, cam->clip_end);
   }
   else if (cam->type == CAM_ORTHO) {
-    double w = cam->ortho_scale / 2;
+    const double w = cam->ortho_scale / 2;
     lineart_matrix_ortho_44d(proj, -w, w, -w / asp, w / asp, cam->clip_start, cam->clip_end);
   }
 
+  double t_start;
+
+  if (G.debug_value == 4000) {
+    t_start = PIL_check_seconds_timer();
+  }
+
   invert_m4_m4(inv, rb->cam_obmat);
   mul_m4db_m4db_m4fl_uniq(result, proj, inv);
   copy_m4_m4_db(proj, result);
@@ -2130,7 +2136,7 @@ static void lineart_main_load_geometries(
       continue;
     }
 
-    if (!lineart_geometry_check_visible(obi->model_view_proj, use_ob)) {
+    if (!lineart_geometry_check_visible(obi->model_view_proj, rb->shift_x, rb->shift_y, use_ob)) {
       if (G.debug_value == 4000) {
         bound_box_discard_count++;
       }
@@ -3023,6 +3029,11 @@ static LineartRenderBuffer *lineart_create_render_buffer(Scene *scene,
   rb->shift_x = fit == CAMERA_SENSOR_FIT_HOR ? c->shiftx : c->shiftx / asp;
   rb->shift_y = fit == CAMERA_SENSOR_FIT_VERT ? c->shifty : c->shifty * asp;
 
+  rb->overscan = lmd->overscan;
+
+  rb->shift_x /= (1 + rb->overscan);
+  rb->shift_y /= (1 + rb->overscan);
+
   rb->crease_threshold = cos(M_PI - lmd->crease_threshold);
   rb->angle_splitting_threshold = lmd->angle_splitting_threshold;
   rb->chaining_image_threshold = lmd->chaining_image_threshold;