- was displaying 1cm as 10mm because of double precission problem.

- typing in numbers without any units will use the units displayed before editing the value.
- fixed some errors

3 files changed, 65 insertions, 14 deletions

diff --git a/source/blender/blenkernel/BKE_unit.h b/source/blender/blenkernel/BKE_unit.h
index 14b805c23f6..6b72c01bf0a 100644
--- a/source/blender/blenkernel/BKE_unit.h
+++ b/source/blender/blenkernel/BKE_unit.h
@@ -34,7 +34,7 @@ extern "C" {
 void	bUnit_AsString(char *str, double value, int prec, int system, int type, int split, int pad);
 
 /* replace units with values, used before python button evaluation */
-int		bUnit_ReplaceString(char *str, char *str_orig, double scale_pref, int system, int type);
+int		bUnit_ReplaceString(char *str, char *str_orig, char *str_prev, double scale_pref, int system, int type);
 
 #ifdef __cplusplus
 }
diff --git a/source/blender/blenkernel/intern/unit.c b/source/blender/blenkernel/intern/unit.c
index 4a5e209a634..eaa90a87691 100644
--- a/source/blender/blenkernel/intern/unit.c
+++ b/source/blender/blenkernel/intern/unit.c
@@ -90,6 +90,7 @@ static struct bUnitDef buNaturalTimeDef[] = {
 };
 static struct bUnitCollection buNaturalTimeCollecton = {buNaturalTimeDef, 3, 0};
 
+#define UNIT_SYSTEM_MAX 3
 static struct bUnitCollection *bUnitSystems[][8] = {
 	{0,0,0,0,0,0,0,0},
 	{0,&buMetricLenCollecton, 0,0,0,0, &buNaturalTimeCollecton,0}, /* metric */
@@ -103,18 +104,25 @@ static bUnitCollection *unit_get_system(int system, int type)
 	return bUnitSystems[system][type]; /* select system to use, metric/imperial/other? */
 }
 
+static bUnitDef *unit_default(bUnitCollection *usys)
+{
+	return &usys->units[usys->base_unit];
+}
+
 static bUnitDef *unit_best_fit(double value, bUnitCollection *usys, bUnitDef *unit_start)
 {
 	bUnitDef *unit;
 	double value_abs= value>0.0?value:-value;
 
 	for(unit= unit_start ? unit_start:usys->units; unit->name; unit++)
-		if (value_abs >= unit->mul)
+		if (value_abs >= unit->mul*0.9999) /* scale down mul so 1cm doesnt convert to 10mm because of float error */
 			return unit;
 
-	return &usys->units[usys->base_unit];
+	return unit_default(usys);
 }
 
+
+
 /* convert into 2 units and 2 values for "2ft, 3inch" syntax */
 static void unit_dual_convert(double value, bUnitCollection *usys,
 		bUnitDef **unit_a, bUnitDef **unit_b, double *value_a, double *value_b)
@@ -140,7 +148,7 @@ static int unit_as_string(char *str, double value, int prec, bUnitCollection *us
 	}
 	else if(value == 0.0) {
 		/* use the default units since there is no way to convert */
-		unit= &usys->units[usys->base_unit];
+		unit= unit_default(usys);
 	}
 	else {
 		unit= unit_best_fit(value, usys, NULL);
@@ -244,7 +252,7 @@ static int unit_scale_str(char *str, char *str_tmp, double scale_pref, bUnitDef
 			/* next char cannot be alphanum */
 			if (!isalpha(*(str_found+len_name))) {
 				int len= strlen(str);
-				int len_num= sprintf(str_tmp, "*%g", scale_pref*unit->mul);
+				int len_num= sprintf(str_tmp, "*%g", unit->mul/scale_pref);
 				memmove(str_found+len_num, str_found+len_name, (len+1)-(int)((str_found+len_name)-str)); /* may grow or shrink the string, 1+ to copy the string terminator */
 				memcpy(str_found, str_tmp, len_num); /* without the string terminator */
 				change= 1;
@@ -256,7 +264,6 @@ static int unit_scale_str(char *str, char *str_tmp, double scale_pref, bUnitDef
 
 static int unit_replace(char *str, char *str_tmp, double scale_pref, bUnitDef *unit)
 {	
-	//unit_replace_delimit(str, str_tmp);
 	int change= 0;
 	change |= unit_scale_str(str, str_tmp, scale_pref, unit, unit->name_short);
 	change |= unit_scale_str(str, str_tmp, scale_pref, unit, unit->name_plural);
@@ -273,11 +280,14 @@ static int unit_replace(char *str, char *str_tmp, double scale_pref, bUnitDef *u
  * 10.1km -> 10.1*1000.0
  * ...will be resolved by python.
  * 
+ * str_prev is optional, when valid it is used to get a base unit when none is set.
+ *
  * return true of a change was made.
  */
-int bUnit_ReplaceString(char *str, char *str_orig, double scale_pref, int system, int type)
+int bUnit_ReplaceString(char *str, char *str_orig, char *str_prev, double scale_pref, int system, int type)
 {
 	bUnitCollection *usys = unit_get_system(system, type);
+
 	bUnitDef *unit;
 	char str_tmp[256];
 	int change= 0;
@@ -287,14 +297,53 @@ int bUnit_ReplaceString(char *str, char *str_orig, double scale_pref, int system
 	if(usys==NULL || usys->units[0].name==NULL) {
 		return 0;
 	}
-
-	scale_pref= 1.0/scale_pref;
 	
 	for(unit= usys->units; unit->name; unit++) {
 		/* incase there are multiple instances */
 		while(unit_replace(str, str_tmp, scale_pref, unit))
 			change= 1;
 	}
+	unit= NULL;
+
+	{
+		/* try other unit systems now, so we can evaluate imperial when metric is set for eg. */
+		bUnitCollection *usys_iter;
+		int system_iter;
+
+		for(system_iter= 1; system_iter<UNIT_SYSTEM_MAX; system_iter++) {
+			if (system_iter != system) {
+				usys_iter= unit_get_system(system_iter, type);
+				for(unit= usys_iter->units; unit->name; unit++) {
+					/* incase there are multiple instances */
+					while(unit_replace(str, str_tmp, scale_pref, unit))
+						change= 1;
+				}
+			}
+		}
+	}
+	unit= NULL;
+
+	if(change==0) {
+		/* no units given so infer a unit from the previous string or default */
+		if(str_prev) {
+			/* see which units the original value had */
+			strcpy(str, str_prev); /* temp overwrite */
+			for(unit= usys->units; unit->name; unit++) {
+				if (unit_replace(str, str_tmp, scale_pref, unit))
+					break;
+			}
+			strcpy(str, str_orig); /* temp overwrite */
+		}
+
+		if(unit==NULL)
+			unit= unit_default(usys);
+
+		/* add the unit prefic and re-run */
+		sprintf(str_tmp, "%s %s", str, unit->name);
+
+		return bUnit_ReplaceString(str, str_tmp, NULL, scale_pref, system, type);
+	}
+
 	// printf("replace %s\n", str);
 	return change;
 }
diff --git a/source/blender/editors/interface/interface.c b/source/blender/editors/interface/interface.c
index 0451cd69dff..878f1bef5cf 100644
--- a/source/blender/editors/interface/interface.c
+++ b/source/blender/editors/interface/interface.c
@@ -1327,14 +1327,14 @@ static double ui_get_but_scale_unit(uiBut *but, double value)
 static void ui_get_but_string_unit(uiBut *but, char *str, double value, int pad)
 {
 	int do_split= U.unit_flag & USER_UNIT_OPT_SPLIT ? 1:0;
-	int unit_system=  RNA_SUBTYPE_UNIT_VALUE(RNA_property_subtype(but->rnaprop));
+	int unit_type=  RNA_SUBTYPE_UNIT_VALUE(RNA_property_subtype(but->rnaprop));
 	int precission= but->a2;
 
 	/* Sanity checks */
 	if(precission>4)		precission= 4;
 	else if(precission==0)	precission= 2;
 
-	bUnit_AsString(str, ui_get_but_scale_unit(but, value), precission, U.unit_system, unit_system, do_split, pad);
+	bUnit_AsString(str, ui_get_but_scale_unit(but, value), precission, U.unit_system, unit_type, do_split, pad);
 }
 
 
@@ -1473,9 +1473,11 @@ int ui_set_but_string(bContext *C, uiBut *but, const char *str)
 #ifndef DISABLE_PYTHON
 		{
 			char str_unit_convert[256];
-			int change= -1;
-			if(U.unit_system != USER_UNIT_NONE) {
-				bUnit_ReplaceString(str_unit_convert, str, ui_get_but_scale_unit(but, 1.0), U.unit_system, RNA_SUBTYPE_UNIT_VALUE(RNA_property_subtype(but->rnaprop)));
+			int unit_type=  RNA_SUBTYPE_UNIT_VALUE(RNA_property_subtype(but->rnaprop));
+
+			if(U.unit_system != USER_UNIT_NONE && unit_type) {
+				/* ugly, use the draw string to get the value, this could cause problems if it includes some text which resolves to a unit */
+				bUnit_ReplaceString(str_unit_convert, str, but->drawstr, ui_get_but_scale_unit(but, 1.0), U.unit_system, unit_type);
 			}
 			else {
 				strcpy(str_unit_convert, str);