static
bool
MyKnob
(
const
char
*
label
,
float
*
p_value
,
float
v_min
,
float
v_max
)
{
ImGuiIO
&
io
=
ImGui
::
GetIO
(
)
;
ImGuiStyle
&
style
=
ImGui
::
GetStyle
(
)
;
float
radius_outer
=
20.0f
;
ImVec2 pos
=
ImGui
::
GetCursorScreenPos
(
)
;
ImVec2 center
=
ImVec2
(
pos
.
x
+
radius_outer
,
pos
.
y
+
radius_outer
)
;
float
line_height
=
ImGui
::
GetTextLineHeight
(
)
;
ImDrawList
*
draw_list
=
ImGui
::
GetWindowDrawList
(
)
;
float
ANGLE_MIN
=
3.141592f
*
0.75f
;
float
ANGLE_MAX
=
3.141592f
*
2.25f
;
ImGui
::
InvisibleButton
(
label
,
ImVec2
(
radius_outer
*
2
,
radius_outer
*
2
+
line_height
+
style
.
ItemInnerSpacing
.
y
)
)
;
bool
value_changed
=
false
;
bool
is_active
=
ImGui
::
IsItemActive
(
)
;
bool
is_hovered
=
ImGui
::
IsItemActive
(
)
;
if
(
is_active
&&
io
.
MouseDelta
.
x
!=
0.0f
)
{
float
step
=
(
v_max
-
v_min
)
/
200.0f
;
*
p_value
+=
io
.
MouseDelta
.
x
*
step
;
if
(
*
p_value

v_max
)
*
p_value
=
v_max
;
value_changed
=
true
;
}
float
t
=
(
*
p_value
-
v_min
)
/
(
v_max
-
v_min
)
;
float
angle
=
ANGLE_MIN
+
(
ANGLE_MAX
-
ANGLE_MIN
)
*
t
;
float
angle_cos
=
cosf
(
angle
)
,
angle_sin
=
sinf
(
angle
)
;
float
radius_inner
=
radius_outer
*
0.40f
;
draw_list
->
AddCircleFilled
(
center
,
radius_outer
,
ImGui
::
GetColorU32
(
ImGuiCol_FrameBg
)
,
16
)
;
draw_list
->
AddLine
(
ImVec2
(
center
.
x
+
angle_cos
*
radius_inner
,
center
.
y
+
angle_sin
*
radius_inner
)
,
ImVec2
(
center
.
x
+
angle_cos
*
(
radius_outer
-
2
)
,
center
.
y
+
angle_sin
*
(
radius_outer
-
2
)
)
,
ImGui
::
GetColorU32
(
ImGuiCol_SliderGrabActive
)
,
2.0f
)
;
draw_list
->
AddCircleFilled
(
center
,
radius_inner
,
ImGui
::
GetColorU32
(
is_active
?
ImGuiCol_FrameBgActive
:
is_hovered
?
ImGuiCol_FrameBgHovered
:
ImGuiCol_FrameBg
)
,
16
)
;
draw_list
->
AddText
(
ImVec2
(
pos
.
x
,
pos
.
y
+
radius_outer
*
2
+
style
.
ItemInnerSpacing
.
y
)
,
ImGui
::
GetColorU32
(
ImGuiCol_Text
)
,
label
)
;
if
(
is_active
||
is_hovered
)
{
ImGui
::
SetNextWindowPos
(
ImVec2
(
pos
.
x
-
style
.
WindowPadding
.
x
,
pos
.
y
-
line_height
-
style
.
ItemInnerSpacing
.
y
-
style
.
WindowPadding
.
y
)
)
;
ImGui
::
BeginTooltip
(
)
;
ImGui
::
Text
(
"%.3f"
,
*
p_value
)
;
ImGui
::
EndTooltip
(
)
;
}
return
value_changed
;
}