Removed support for legacy arithmetic operators (+*/) when inputing text into a slider/drag. (#4917, #3184)

docs/CHANGELOG.txt

@@ -38,6 +38,9 @@ HOW TO UPDATE?
 Breaking Changes:
 
 - Removed support for pre-C++11 compilers. We'll stop supporting VS2010. (#4537)
+- Removed support for legacy arithmetic operators (+,+-,*,/) when inputing text into a slider/drag. (#4917, #3184)
+  This doesn't break any api/code but a feature that was accessible by end-users (which seemingly no one used).
+  (Instead you may implement custom expression evaluators to provide a better version of this).
 - Reworked IO mouse input API: (#4858) [@thedmd, @ocornut]
   - Added io.AddMousePosEvent(), AddMouseButtonEvent(), AddMouseWheelEvent() functions,
     obsoleting writing directly to io.MousePos, io.MouseDown[], io.MouseWheel, etc.
@@ -102,6 +105,7 @@ Other Changes:
   which would makes the draw operation of some backends assert (e.g. Metal with debugging). (#4857)
 - Tables, ImDrawListSplitter: Fixed erroneously stripping trailing ImDrawList::AddCallback() when submitted in
   last column or last channel and when there are no other drawing operation. (#4843, #4844) [@hoffstadt]
+- Sliders, Drags: Fixed text input of values with a leading sign, common when using a format enforcing sign. (#4917)
 - Platform IME: changed io.ImeSetInputScreenPosFn() to io.SetPlatformImeDataFn() API,
   now taking a ImGuiPlatformImeData structure which we can more easily extend in the future.
 - Platform IME: moved io.ImeWindowHandle to GetMainViewport()->PlatformHandleRaw.

docs/TODO.txt

@@ -113,7 +113,6 @@ It's mostly a bunch of personal notes, probably incomplete. Feel free to query i
  - input number: optional range min/max for Input*() functions
  - input number: holding [-]/[+] buttons could increase the step speed non-linearly (or user-controlled)
  - input number: use mouse wheel to step up/down
- - input number: applying arithmetics ops (+,-,*,/) messes up with text edit undo stack.
 
  - layout: helper or a way to express ImGui::SameLine(ImGui::GetCursorStartPos().x + ImGui::CalcItemWidth() + ImGui::GetStyle().ItemInnerSpacing.x); in a simpler manner.
  - layout, font: horizontal tab support, A) text mode: forward only tabs (e.g. every 4 characters/N pixels from pos x1), B) manual mode: explicit tab stops acting as mini columns, no clipping (for menu items, many kind of uses, also vaguely relate to #267, #395)

imgui.cpp

@@ -128,7 +128,6 @@ CODE
    - CTRL+X,CTRL+C,CTRL+V to use OS clipboard/
    - CTRL+Z,CTRL+Y to undo/redo.
    - ESCAPE to revert text to its original value.
-   - You can apply arithmetic operators +,*,/ on numerical values. Use +- to subtract (because - would set a negative value!)
    - Controls are automatically adjusted for OSX to match standard OSX text editing operations.
  - General Keyboard controls: enable with ImGuiConfigFlags_NavEnableKeyboard.
  - General Gamepad controls: enable with ImGuiConfigFlags_NavEnableGamepad. See suggested mappings in imgui.h ImGuiNavInput_ + download PNG/PSD at http://dearimgui.org/controls_sheets
@@ -386,6 +385,7 @@ CODE
  When you are not sure about an old symbol or function name, try using the Search/Find function of your IDE to look for comments or references in all imgui files.
  You can read releases logs https://github.com/ocornut/imgui/releases for more details.
 
+ - 2022/01/19 (1.87) - sliders, drags: removed support for legacy arithmetic operators (+,+-,*,/) when inputing text. This doesn't break any api/code but a feature that used to be accessible by end-users (which seemingly no one used).
  - 2022/01/17 (1.87) - inputs: reworked mouse IO.
                         - Backend writing to io.MousePos               -> backend should call io.AddMousePosEvent()
                         - Backend writing to io.MouseDown[]            -> backend should call io.AddMouseButtonEvent()

imgui.h

@@ -65,7 +65,7 @@ Index of this file:
 // Version
 // (Integer encoded as XYYZZ for use in #if preprocessor conditionals. Work in progress versions typically starts at XYY99 then bounce up to XYY00, XYY01 etc. when release tagging happens)
 #define IMGUI_VERSION               "1.87 WIP"
-#define IMGUI_VERSION_NUM           18608
+#define IMGUI_VERSION_NUM           18609
 #define IMGUI_CHECKVERSION()        ImGui::DebugCheckVersionAndDataLayout(IMGUI_VERSION, sizeof(ImGuiIO), sizeof(ImGuiStyle), sizeof(ImVec2), sizeof(ImVec4), sizeof(ImDrawVert), sizeof(ImDrawIdx))
 #define IMGUI_HAS_TABLE
 

imgui_demo.cpp

@@ -229,7 +229,6 @@ void ImGui::ShowUserGuide()
     ImGui::BulletText("CTRL+X/C/V to use clipboard cut/copy/paste.");
     ImGui::BulletText("CTRL+Z,CTRL+Y to undo/redo.");
     ImGui::BulletText("ESCAPE to revert.");
-    ImGui::BulletText("You can apply arithmetic operators +,*,/ on numerical values.\nUse +- to subtract.");
     ImGui::Unindent();
     ImGui::BulletText("With keyboard navigation enabled:");
     ImGui::Indent();
@@ -676,10 +675,6 @@ static void ShowDemoWindowWidgets()
             IMGUI_DEMO_MARKER("Widgets/Basic/InputInt, InputFloat");
             static int i0 = 123;
             ImGui::InputInt("input int", &i0);
-            ImGui::SameLine(); HelpMarker(
-                "You can apply arithmetic operators +,*,/ on numerical values.\n"
-                "  e.g. [ 100 ], input \'*2\', result becomes [ 200 ]\n"
-                "Use +- to subtract.");
 
             static float f0 = 0.001f;
             ImGui::InputFloat("input float", &f0, 0.01f, 1.0f, "%.3f");

imgui_internal.h

@@ -2805,7 +2805,7 @@ namespace ImGui
     IMGUI_API const ImGuiDataTypeInfo*  DataTypeGetInfo(ImGuiDataType data_type);
     IMGUI_API int           DataTypeFormatString(char* buf, int buf_size, ImGuiDataType data_type, const void* p_data, const char* format);
     IMGUI_API void          DataTypeApplyOp(ImGuiDataType data_type, int op, void* output, const void* arg_1, const void* arg_2);
-    IMGUI_API bool          DataTypeApplyOpFromText(const char* buf, const char* initial_value_buf, ImGuiDataType data_type, void* p_data, const char* format);
+    IMGUI_API bool          DataTypeApplyFromText(const char* buf, ImGuiDataType data_type, void* p_data, const char* format);
     IMGUI_API int           DataTypeCompare(ImGuiDataType data_type, const void* arg_1, const void* arg_2);
     IMGUI_API bool          DataTypeClamp(ImGuiDataType data_type, void* p_data, const void* p_min, const void* p_max);
 

imgui_widgets.cpp

@@ -1992,24 +1992,10 @@ void ImGui::DataTypeApplyOp(ImGuiDataType data_type, int op, void* output, const
 
 // User can input math operators (e.g. +100) to edit a numerical values.
 // NB: This is _not_ a full expression evaluator. We should probably add one and replace this dumb mess..
-bool ImGui::DataTypeApplyOpFromText(const char* buf, const char* initial_value_buf, ImGuiDataType data_type, void* p_data, const char* format)
+bool ImGui::DataTypeApplyFromText(const char* buf, ImGuiDataType data_type, void* p_data, const char* format)
 {
     while (ImCharIsBlankA(*buf))
         buf++;
-
-    // We don't support '-' op because it would conflict with inputing negative value.
-    // Instead you can use +-100 to subtract from an existing value
-    char op = buf[0];
-    if (op == '+' || op == '*' || op == '/')
-    {
-        buf++;
-        while (ImCharIsBlankA(*buf))
-            buf++;
-    }
-    else
-    {
-        op = 0;
-    }
     if (!buf[0])
         return false;
 
@@ -2021,54 +2007,11 @@ bool ImGui::DataTypeApplyOpFromText(const char* buf, const char* initial_value_b
     if (format == NULL)
         format = type_info->ScanFmt;
 
-    // FIXME-LEGACY: The aim is to remove those operators and write a proper expression evaluator at some point..
+    if (data_type == ImGuiDataType_S32 || data_type == ImGuiDataType_U32 || data_type == ImGuiDataType_S64 || data_type == ImGuiDataType_U64 || data_type == ImGuiDataType_Float || data_type == ImGuiDataType_Double)
-    int arg1i = 0;
-    if (data_type == ImGuiDataType_S32)
     {
-        int* v = (int*)p_data;
+        // For float/double we have to ignore format with precision (e.g. "%.2f") because sscanf doesn't take them in, so force them into %f and %lf
-        int arg0i = *v;
+        if (data_type == ImGuiDataType_Float || data_type == ImGuiDataType_Double)
-        float arg1f = 0.0f;
+            format = type_info->ScanFmt;
-        if (op && sscanf(initial_value_buf, format, &arg0i) < 1)
-            return false;
-        // Store operand in a float so we can use fractional value for multipliers (*1.1), but constant always parsed as integer so we can fit big integers (e.g. 2000000003) past float precision
-        if (op == '+')      { if (sscanf(buf, "%d", &arg1i)) *v = (int)(arg0i + arg1i); }                   // Add (use "+-" to subtract)
-        else if (op == '*') { if (sscanf(buf, "%f", &arg1f)) *v = (int)(arg0i * arg1f); }                   // Multiply
-        else if (op == '/') { if (sscanf(buf, "%f", &arg1f) && arg1f != 0.0f) *v = (int)(arg0i / arg1f); }  // Divide
-        else                { if (sscanf(buf, format, &arg1i) == 1) *v = arg1i; }                           // Assign constant
-    }
-    else if (data_type == ImGuiDataType_Float)
-    {
-        // For floats we have to ignore format with precision (e.g. "%.2f") because sscanf doesn't take them in
-        format = "%f";
-        float* v = (float*)p_data;
-        float arg0f = *v, arg1f = 0.0f;
-        if (op && sscanf(initial_value_buf, format, &arg0f) < 1)
-            return false;
-        if (sscanf(buf, format, &arg1f) < 1)
-            return false;
-        if (op == '+')      { *v = arg0f + arg1f; }                    // Add (use "+-" to subtract)
-        else if (op == '*') { *v = arg0f * arg1f; }                    // Multiply
-        else if (op == '/') { if (arg1f != 0.0f) *v = arg0f / arg1f; } // Divide
-        else                { *v = arg1f; }                            // Assign constant
-    }
-    else if (data_type == ImGuiDataType_Double)
-    {
-        format = "%lf"; // scanf differentiate float/double unlike printf which forces everything to double because of ellipsis
-        double* v = (double*)p_data;
-        double arg0f = *v, arg1f = 0.0;
-        if (op && sscanf(initial_value_buf, format, &arg0f) < 1)
-            return false;
-        if (sscanf(buf, format, &arg1f) < 1)
-            return false;
-        if (op == '+')      { *v = arg0f + arg1f; }                    // Add (use "+-" to subtract)
-        else if (op == '*') { *v = arg0f * arg1f; }                    // Multiply
-        else if (op == '/') { if (arg1f != 0.0f) *v = arg0f / arg1f; } // Divide
-        else                { *v = arg1f; }                            // Assign constant
-    }
-    else if (data_type == ImGuiDataType_U32 || data_type == ImGuiDataType_S64 || data_type == ImGuiDataType_U64)
-    {
-        // All other types assign constant
-        // We don't bother handling support for legacy operators since they are a little too crappy. Instead we will later implement a proper expression evaluator in the future.
         if (sscanf(buf, format, p_data) < 1)
             return false;
     }
@@ -3387,8 +3330,6 @@ bool ImGui::TempInputText(const ImRect& bb, ImGuiID id, const char* label, char*
 // However this may not be ideal for all uses, as some user code may break on out of bound values.
 bool ImGui::TempInputScalar(const ImRect& bb, ImGuiID id, const char* label, ImGuiDataType data_type, void* p_data, const char* format, const void* p_clamp_min, const void* p_clamp_max)
 {
-    ImGuiContext& g = *GImGui;
-
     char fmt_buf[32];
     char data_buf[32];
     format = ImParseFormatTrimDecorations(format, fmt_buf, IM_ARRAYSIZE(fmt_buf));
@@ -3406,7 +3347,7 @@ bool ImGui::TempInputScalar(const ImRect& bb, ImGuiID id, const char* label, ImG
         memcpy(&data_backup, p_data, data_type_size);
 
         // Apply new value (or operations) then clamp
-        DataTypeApplyOpFromText(data_buf, g.InputTextState.InitialTextA.Data, data_type, p_data, NULL);
+        DataTypeApplyFromText(data_buf, data_type, p_data, NULL);
         if (p_clamp_min || p_clamp_max)
         {
             if (p_clamp_min && p_clamp_max && DataTypeCompare(data_type, p_clamp_min, p_clamp_max) > 0)
@@ -3453,7 +3394,7 @@ bool ImGui::InputScalar(const char* label, ImGuiDataType data_type, void* p_data
         PushID(label);
         SetNextItemWidth(ImMax(1.0f, CalcItemWidth() - (button_size + style.ItemInnerSpacing.x) * 2));
         if (InputText("", buf, IM_ARRAYSIZE(buf), flags)) // PushId(label) + "" gives us the expected ID from outside point of view
-            value_changed = DataTypeApplyOpFromText(buf, g.InputTextState.InitialTextA.Data, data_type, p_data, format);
+            value_changed = DataTypeApplyFromText(buf, data_type, p_data, format);
 
         // Step buttons
         const ImVec2 backup_frame_padding = style.FramePadding;
@@ -3490,7 +3431,7 @@ bool ImGui::InputScalar(const char* label, ImGuiDataType data_type, void* p_data
     else
     {
         if (InputText(label, buf, IM_ARRAYSIZE(buf), flags))
-            value_changed = DataTypeApplyOpFromText(buf, g.InputTextState.InitialTextA.Data, data_type, p_data, format);
+            value_changed = DataTypeApplyFromText(buf, data_type, p_data, format);
     }
     if (value_changed)
         MarkItemEdited(g.LastItemData.ID);