DragBehavior: Moving code around, in what should be a no-op, to simplify upcoming Nav diff (#323, #180)

imgui.cpp

@@ -6769,32 +6769,33 @@ bool ImGui::DragBehavior(const ImRect& frame_bb, ImGuiID id, float* v, float v_s
                 g.DragLastMouseDelta = ImVec2(0.f, 0.f);
             }
 
+            if (v_speed == 0.0f && (v_max - v_min) != 0.0f && (v_max - v_min) < FLT_MAX)
+                v_speed = (v_max - v_min) * g.DragSpeedDefaultRatio;
+
             float v_cur = g.DragCurrentValue;
             const ImVec2 mouse_drag_delta = GetMouseDragDelta(0, 1.0f);
-            if (fabsf(mouse_drag_delta.x - g.DragLastMouseDelta.x) > 0.0f)
+            float adjust_delta = mouse_drag_delta.x - g.DragLastMouseDelta.x;
+            if (g.IO.KeyShift && g.DragSpeedScaleFast >= 0.0f)
+                adjust_delta *= g.DragSpeedScaleFast;
+            if (g.IO.KeyAlt && g.DragSpeedScaleSlow >= 0.0f)
+                adjust_delta *= g.DragSpeedScaleSlow;
+            adjust_delta *= v_speed;
+
+            if (fabsf(adjust_delta) > 0.0f)
             {
-                float speed = v_speed;
-                if (speed == 0.0f && (v_max - v_min) != 0.0f && (v_max - v_min) < FLT_MAX)
-                    speed = (v_max - v_min) * g.DragSpeedDefaultRatio;
-                if (g.IO.KeyShift && g.DragSpeedScaleFast >= 0.0f)
-                    speed = speed * g.DragSpeedScaleFast;
-                if (g.IO.KeyAlt && g.DragSpeedScaleSlow >= 0.0f)
-                    speed = speed * g.DragSpeedScaleSlow;
-
-                float delta = (mouse_drag_delta.x - g.DragLastMouseDelta.x) * speed;
                 if (fabsf(power - 1.0f) > 0.001f)
                 {
                     // Logarithmic curve on both side of 0.0
                     float v0_abs = v_cur >= 0.0f ? v_cur : -v_cur;
                     float v0_sign = v_cur >= 0.0f ? 1.0f : -1.0f;
-                    float v1 = powf(v0_abs, 1.0f / power) + (delta * v0_sign);
+                    float v1 = powf(v0_abs, 1.0f / power) + (adjust_delta * v0_sign);
                     float v1_abs = v1 >= 0.0f ? v1 : -v1;
                     float v1_sign = v1 >= 0.0f ? 1.0f : -1.0f;          // Crossed sign line
                     v_cur = powf(v1_abs, power) * v0_sign * v1_sign;    // Reapply sign
                 }
                 else
                 {
-                    v_cur += delta;
+                    v_cur += adjust_delta;
                 }
                 g.DragLastMouseDelta.x = mouse_drag_delta.x;