[Bf-blender-cvs] [f33e6e0d8c6] master: Cleanup: move camera-view pan/zoom into utility functions

[Campbell Barton]

Commit: f33e6e0d8c607eb33b1eb0c587b4e43cde30d5e1
Author: Campbell Barton
Date:   Fri Feb 18 16:43:10 2022 +1100
Branches: master
https://developer.blender.org/rBf33e6e0d8c607eb33b1eb0c587b4e43cde30d5e1

Cleanup: move camera-view pan/zoom into utility functions

===================================================================

M	source/blender/editors/include/ED_view3d.h
M	source/blender/editors/space_view3d/view3d_navigate.c
M	source/blender/editors/space_view3d/view3d_utils.c

===================================================================

diff --git a/source/blender/editors/include/ED_view3d.h b/source/blender/editors/include/ED_view3d.h
index 46c9a1973eb..18b63403fcb 100644
--- a/source/blender/editors/include/ED_view3d.h
+++ b/source/blender/editors/include/ED_view3d.h
@@ -1078,6 +1078,20 @@ bool ED_view3d_persp_ensure(const struct Depsgraph *depsgraph,
                             struct View3D *v3d,
                             struct ARegion *region);
 
+/* Camera view functions. */
+
+/**
+ * Utility to scale zoom level when in camera-view #RegionView3D.camzoom and apply limits.
+ * \return true a change was made.
+ */
+bool ED_view3d_camera_view_zoom_scale(struct RegionView3D *rv3d, const float scale);
+/**
+ * Utility to pan when in camera view.
+ * \param event_ofs: The offset the pan in screen (pixel) coordinates.
+ * \return true when a change was made.
+ */
+bool ED_view3d_camera_view_pan(struct ARegion *region, const float event_ofs[2]);
+
 /* Camera lock functions */
 
 /**
diff --git a/source/blender/editors/space_view3d/view3d_navigate.c b/source/blender/editors/space_view3d/view3d_navigate.c
index 0305989d142..d1e7b5891e9 100644
--- a/source/blender/editors/space_view3d/view3d_navigate.c
+++ b/source/blender/editors/space_view3d/view3d_navigate.c
@@ -549,11 +549,11 @@ void viewmove_apply(ViewOpsData *vod, int x, int y)
     vod->rv3d->ofs_lock[1] -= ((vod->prev.event_xy[1] - y) * 2.0f) / (float)vod->region->winy;
   }
   else if ((vod->rv3d->persp == RV3D_CAMOB) && !ED_view3d_camera_lock_check(vod->v3d, vod->rv3d)) {
-    const float zoomfac = BKE_screen_view3d_zoom_to_fac(vod->rv3d->camzoom) * 2.0f;
-    vod->rv3d->camdx += (vod->prev.event_xy[0] - x) / (vod->region->winx * zoomfac);
-    vod->rv3d->camdy += (vod->prev.event_xy[1] - y) / (vod->region->winy * zoomfac);
-    CLAMP(vod->rv3d->camdx, -1.0f, 1.0f);
-    CLAMP(vod->rv3d->camdy, -1.0f, 1.0f);
+    const float event_ofs[2] = {
+        vod->prev.event_xy[0] - x,
+        vod->prev.event_xy[1] - y,
+    };
+    ED_view3d_camera_view_pan(vod->region, event_ofs);
   }
   else {
     float dvec[3];
diff --git a/source/blender/editors/space_view3d/view3d_utils.c b/source/blender/editors/space_view3d/view3d_utils.c
index 8a219cd96d1..3e788f2d643 100644
--- a/source/blender/editors/space_view3d/view3d_utils.c
+++ b/source/blender/editors/space_view3d/view3d_utils.c
@@ -509,6 +509,39 @@ bool ED_view3d_persp_ensure(const Depsgraph *depsgraph, View3D *v3d, ARegion *re
 
 /** \} */
 
+/* -------------------------------------------------------------------- */
+/** \name Camera View Utilities
+ *
+ * Utilities for manipulating the camera-view.
+ * \{ */
+
+bool ED_view3d_camera_view_zoom_scale(RegionView3D *rv3d, const float scale)
+{
+  const float camzoom_init = rv3d->camzoom;
+  float zoomfac = BKE_screen_view3d_zoom_to_fac(rv3d->camzoom);
+  /* Clamp both before and after conversion to prevent NAN on negative values. */
+
+  zoomfac = zoomfac * scale;
+  CLAMP(zoomfac, RV3D_CAMZOOM_MIN_FACTOR, RV3D_CAMZOOM_MAX_FACTOR);
+  rv3d->camzoom = BKE_screen_view3d_zoom_from_fac(zoomfac);
+  CLAMP(rv3d->camzoom, RV3D_CAMZOOM_MIN, RV3D_CAMZOOM_MAX);
+  return (rv3d->camzoom != camzoom_init);
+}
+
+bool ED_view3d_camera_view_pan(ARegion *region, const float event_ofs[2])
+{
+  RegionView3D *rv3d = region->regiondata;
+  const float camdxy_init[2] = {rv3d->camdx, rv3d->camdy};
+  const float zoomfac = BKE_screen_view3d_zoom_to_fac(rv3d->camzoom) * 2.0f;
+  rv3d->camdx += event_ofs[0] / (region->winx * zoomfac);
+  rv3d->camdy += event_ofs[1] / (region->winy * zoomfac);
+  CLAMP(rv3d->camdx, -1.0f, 1.0f);
+  CLAMP(rv3d->camdy, -1.0f, 1.0f);
+  return (camdxy_init[0] != rv3d->camdx) || (camdxy_init[1] != rv3d->camdy);
+}
+
+/** \} */
+
 /* -------------------------------------------------------------------- */
 /** \name Camera Lock API
  *