UI: use shared toolbar region callbacks

Image toolbar now starts with a single column width
and snaps to button increments.

1 files changed, 89 insertions, 0 deletions

diff --git a/source/blender/editors/screen/area_utils.c b/source/blender/editors/screen/area_utils.c
new file mode 100644
index 00000000000..53e2f96d6c4
--- /dev/null
+++ b/source/blender/editors/screen/area_utils.c
@@ -0,0 +1,89 @@
+/*
+ * ***** 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.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file blender/editors/screen/area_utils.c
+ *  \ingroup edscr
+ *
+ * Helper functions for area/region API.
+ */
+
+#include "DNA_userdef_types.h"
+
+#include "BLI_blenlib.h"
+#include "BLI_utildefines.h"
+
+#include "BKE_context.h"
+
+#include "RNA_access.h"
+#include "RNA_types.h"
+
+#include "WM_api.h"
+#include "WM_message.h"
+
+#include "ED_screen.h"
+
+#include "UI_interface.h"
+
+/* -------------------------------------------------------------------- */
+/** \name Generic Tool System Region Callbacks
+ * \{ */
+
+/**
+ * Callback for #ARegionType.message_subscribe
+ */
+void ED_region_generic_tools_region_message_subscribe(
+        const struct bContext *UNUSED(C),
+        struct WorkSpace *UNUSED(workspace), struct Scene *UNUSED(scene),
+        struct bScreen *UNUSED(screen), struct ScrArea *UNUSED(sa), struct ARegion *ar,
+        struct wmMsgBus *mbus)
+{
+	wmMsgSubscribeValue msg_sub_value_region_tag_redraw = {
+		.owner = ar,
+		.user_data = ar,
+		.notify = ED_region_do_msg_notify_tag_redraw,
+	};
+	WM_msg_subscribe_rna_anon_prop(mbus, WorkSpace, tools, &msg_sub_value_region_tag_redraw);
+}
+
+/**
+ * Callback for #ARegionType.snap_size
+ */
+int ED_region_generic_tools_region_snap_size(const ARegion *ar, int size, int axis)
+{
+	if (axis == 0) {
+		/* Note, this depends on the icon size: see #ICON_DEFAULT_HEIGHT_TOOLBAR. */
+		const float snap_units[] = {2 + 0.8f, 4 + 0.8f};
+		const float aspect = BLI_rctf_size_x(&ar->v2d.cur) / (BLI_rcti_size_x(&ar->v2d.mask) + 1);
+		int best_diff = INT_MAX;
+		int best_size = size;
+		for (uint i = 0; i < ARRAY_SIZE(snap_units); i += 1) {
+			const int test_size = (snap_units[i] * U.widget_unit) / (UI_DPI_FAC * aspect);
+			const int test_diff = ABS(test_size - size);
+			if (test_diff < best_diff) {
+				best_size = test_size;
+				best_diff = test_diff;
+			}
+		}
+		return best_size;
+	}
+	return size;
+}
+
+/** \} */