Units: Support for fixed units

Users can select the main unit they want to use now.
Previously the displayed unit always depended on the magnitude of the value.
The old behavior can be restored by switching to the "Adaptive" mode for length, mass and time units.

Meters, kilograms and seconds are the default units for new and old scenes.

The selected unit is also the default unit for user input.
E.g. if cm is selected, whenever the user inputs a unitless number into a field of type length, it will be interpreted as cm.

Reviewer: brecht

Differential: https://developer.blender.org/D3740

1 files changed, 30 insertions, 24 deletions

diff --git a/source/blender/editors/util/numinput.c b/source/blender/editors/util/numinput.c
index 98e7e5ba897..887c85300d1 100644
--- a/source/blender/editors/util/numinput.c
+++ b/source/blender/editors/util/numinput.c
@@ -254,6 +254,32 @@ static bool editstr_insert_at_cursor(NumInput *n, const char *buf, const int buf
 	return true;
 }
 
+bool user_string_to_number(bContext *C, const char *str, const UnitSettings *unit, int type, double *r_value)
+{
+#ifdef WITH_PYTHON
+	double unit_scale = BKE_scene_unit_scale(unit, type, 1.0);
+	if (!bUnit_ContainsUnit(str, unit->system, type)) {
+		int success = BPY_execute_string_as_number(C, NULL, str, true, r_value);
+		*r_value *= bUnit_PreferredUnitScalar(unit, type);
+		*r_value /= unit_scale;
+		return success;
+	}
+	else {
+		char str_unit_convert[256];
+		BLI_strncpy(str_unit_convert, str, sizeof(str_unit_convert));
+		bUnit_ReplaceString(
+		        str_unit_convert, sizeof(str_unit_convert), str,
+		        unit_scale, unit->system, type);
+
+		return BPY_execute_string_as_number(C, NULL, str_unit_convert, true, r_value);
+	}
+#else
+	*r_value = atof(str);
+	return true;
+#endif
+}
+
+
 static bool editstr_is_simple_numinput(const char ascii)
 {
 	if (ascii >= '0' && ascii <= '9') {
@@ -519,38 +545,18 @@ bool handleNumInput(bContext *C, NumInput *n, const wmEvent *event)
 	/* At this point, our value has changed, try to interpret it with python (if str is not empty!). */
 	if (n->str[0]) {
 		const float val_prev = n->val[idx];
-		double val;
-#ifdef WITH_PYTHON
 		Scene *sce = CTX_data_scene(C);
-		char str_unit_convert[NUM_STR_REP_LEN * 6];  /* Should be more than enough! */
-		const char *default_unit = NULL;
 
-		/* Use scale_length if needed! */
-		const float fac = (float)BKE_scene_unit_scale(&sce->unit, n->unit_type[idx], 1.0);
-
-		/* Make radian default unit when needed. */
-		if (n->unit_use_radians && n->unit_type[idx] == B_UNIT_ROTATION) {
-			default_unit = "r";
-		}
-
-		BLI_strncpy(str_unit_convert, n->str, sizeof(str_unit_convert));
-
-		bUnit_ReplaceString(str_unit_convert, sizeof(str_unit_convert), default_unit, fac,
-		                    n->unit_sys, n->unit_type[idx]);
+		double val;
+		int success = user_string_to_number(C, n->str, &sce->unit, n->unit_type[idx], &val);
 
-		/* Note: with angles, we always get values as radians here... */
-		if (BPY_execute_string_as_number(C, NULL, str_unit_convert, false, &val)) {
+		if (success) {
 			n->val[idx] = (float)val;
 			n->val_flag[idx] &= ~NUM_INVALID;
 		}
 		else {
 			n->val_flag[idx] |= NUM_INVALID;
-		}
-#else  /* Very unlikely, but does not harm... */
-		val = atof(n->str);
-		n->val[idx] = (float)val;
-		UNUSED_VARS(C);
-#endif  /* WITH_PYTHON */
+	}
 
 
 #ifdef USE_FAKE_EDIT