Drags, Slider: added ImGuiSliderFlags_ClampOnInput, ImGuiSliderFlags_ClampZeroRange. (#7968, #3361, #76)

docs/CHANGELOG.txt

@@ -41,6 +41,13 @@ HOW TO UPDATE?
 
 Breaking changes:
 
+- Drags: treat v_min==v_max as a valid clamping range when != 0.0f. Zero is still a special
+  value due to legacy reasons, unless using ImGuiSliderFlags_ClampZeroRange. (#7968, #3361, #76)
+- Drags: extended behavior of ImGuiSliderFlags_AlwaysClamp to include _ClampZeroRange.
+  It considers v_min==v_max==0.0f as a valid clamping range (aka edits not allowed).
+  Although unlikely, it you wish to only clamp on text input but want v_min==v_max==0.0f
+  to mean unclamped drags, you can use _ClampOnInput instead of _AlwaysClamp. (#7968, #3361, #76)
+
 Other changes:
 
 - Error Handling: Enabled/improved error recovery systems. (#1651, #5654)
@@ -71,6 +78,13 @@ Other changes:
 - Scrollbar: Shift+Click scroll to clicked location (pre-1.90.8 default). (#8002, #7328)
 - Scrollbar: added io.ConfigScrollbarScrollByPage setting (default to true). (#8002, #7328)
   Set io.ConfigScrollbarScrollByPage=false to enforce always scrolling to clicked location.
+- Drags: ImGuiSliderFlags_AlwaysClamp split into two distinct flags: (#7968, #3361, #76)
+  - ImGuiSliderFlags_AlwaysClamp = ImGuiSliderFlags_ClampOnInput + ImGuiSliderFlags_ClampZeroRange.
+  - Previously _AlwaysClamp only did the equivalent of _ClampOnInput.
+  - Added ImGuiSliderFlags_ClampOnInput which is now a subset of AlwaysClamp.
+    (note that it was the old name of AlwaysClamp, but we are reintroducing that name).
+  - Added ImGuiSliderFlags_ClampZeroRange to enforce clamping even when v_min==v_max==0.0f
+    in drag functions. Sliders are not affected.
 - Tooltips, Drag and Drop: Fixed an issue where the fallback drag and drop payload tooltip
   appeared during drag and drop release.
 - Tooltips, Drag and Drop: Stabilized name of drag and drop tooltip window so that

imgui.cpp

@@ -430,6 +430,9 @@ 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.
 
+ - 2024/10/03 (1.91.3) - drags: treat v_min==v_max as a valid clamping range when != 0.0f. Zero is a still special value due to legacy reasons, unless using ImGuiSliderFlags_ClampZeroRange. (#7968, #3361, #76)
+                       - drags: extended behavior of ImGuiSliderFlags_AlwaysClamp to include _ClampZeroRange. It considers v_min==v_max==0.0f as a valid clamping range (aka edits not allowed).
+                         although unlikely, it you wish to only clamp on text input but want v_min==v_max==0.0f to mean unclamped drags, you can use _ClampOnInput instead of _AlwaysClamp. (#7968, #3361, #76)
  - 2024/08/23 (1.91.1) - renamed ImGuiChildFlags_Border to ImGuiChildFlags_Borders for consistency. kept inline redirection flag.
  - 2024/08/22 (1.91.1) - moved some functions from ImGuiIO to ImGuiPlatformIO structure:
                             - io.GetClipboardTextFn         -> platform_io.Platform_GetClipboardTextFn + changed 'void* user_data' to 'ImGuiContext* ctx'. Pull your user data from platform_io.ClipboardUserData.

imgui.h

@@ -29,7 +29,7 @@
 // Library Version
 // (Integer encoded as XYYZZ for use in #if preprocessor conditionals, e.g. '#if IMGUI_VERSION_NUM >= 12345')
 #define IMGUI_VERSION       "1.91.3 WIP"
-#define IMGUI_VERSION_NUM   19124
+#define IMGUI_VERSION_NUM   19125
 #define IMGUI_HAS_TABLE
 
 /*
@@ -1788,19 +1788,18 @@ enum ImGuiColorEditFlags_
 
 // Flags for DragFloat(), DragInt(), SliderFloat(), SliderInt() etc.
 // We use the same sets of flags for DragXXX() and SliderXXX() functions as the features are the same and it makes it easier to swap them.
-// (Those are per-item flags. There are shared flags in ImGuiIO: io.ConfigDragClickToInputText)
+// (Those are per-item flags. There is shared behavior flag too: ImGuiIO: io.ConfigDragClickToInputText)
 enum ImGuiSliderFlags_
 {
-    ImGuiSliderFlags_None                   = 0,
+    ImGuiSliderFlags_None               = 0,
-    ImGuiSliderFlags_AlwaysClamp            = 1 << 4,       // Clamp value to min/max bounds when input manually with CTRL+Click. By default CTRL+Click allows going out of bounds.
+    ImGuiSliderFlags_Logarithmic        = 1 << 5,       // Make the widget logarithmic (linear otherwise). Consider using ImGuiSliderFlags_NoRoundToFormat with this if using a format-string with small amount of digits.
-    ImGuiSliderFlags_Logarithmic            = 1 << 5,       // Make the widget logarithmic (linear otherwise). Consider using ImGuiSliderFlags_NoRoundToFormat with this if using a format-string with small amount of digits.
+    ImGuiSliderFlags_NoRoundToFormat    = 1 << 6,       // Disable rounding underlying value to match precision of the display format string (e.g. %.3f values are rounded to those 3 digits).
-    ImGuiSliderFlags_NoRoundToFormat        = 1 << 6,       // Disable rounding underlying value to match precision of the display format string (e.g. %.3f values are rounded to those 3 digits).
+    ImGuiSliderFlags_NoInput            = 1 << 7,       // Disable CTRL+Click or Enter key allowing to input text directly into the widget.
-    ImGuiSliderFlags_NoInput                = 1 << 7,       // Disable CTRL+Click or Enter key allowing to input text directly into the widget.
+    ImGuiSliderFlags_WrapAround         = 1 << 8,       // Enable wrapping around from max to min and from min to max. Only supported by DragXXX() functions for now.
-    ImGuiSliderFlags_WrapAround             = 1 << 8,       // Enable wrapping around from max to min and from min to max (only supported by DragXXX() functions for now.
+    ImGuiSliderFlags_ClampOnInput       = 1 << 9,       // Clamp value to min/max bounds when input manually with CTRL+Click. By default CTRL+Click allows going out of bounds.
-    ImGuiSliderFlags_InvalidMask_           = 0x7000000F,   // [Internal] We treat using those bits as being potentially a 'float power' argument from the previous API that has got miscast to this enum, and will trigger an assert if needed.
+    ImGuiSliderFlags_ClampZeroRange     = 1 << 10,      // Clamp even if min==max==0.0f. Otherwise due to legacy reason DragXXX functions don't clamp with those values. When your clamping limits are dynamic you almost always want to use it.
-
+    ImGuiSliderFlags_AlwaysClamp        = ImGuiSliderFlags_ClampOnInput | ImGuiSliderFlags_ClampZeroRange,
-    // Obsolete names
+    ImGuiSliderFlags_InvalidMask_       = 0x7000000F,   // [Internal] We treat using those bits as being potentially a 'float power' argument from the previous API that has got miscast to this enum, and will trigger an assert if needed.
-    //ImGuiSliderFlags_ClampOnInput = ImGuiSliderFlags_AlwaysClamp, // [renamed in 1.79]
 };
 
 // Identify a mouse button.
@@ -3170,8 +3169,8 @@ struct ImDrawList
     //inline  void  AddEllipse(const ImVec2& center, float radius_x, float radius_y, ImU32 col, float rot = 0.0f, int num_segments = 0, float thickness = 1.0f) { AddEllipse(center, ImVec2(radius_x, radius_y), col, rot, num_segments, thickness); } // OBSOLETED in 1.90.5 (Mar 2024)
     //inline  void  AddEllipseFilled(const ImVec2& center, float radius_x, float radius_y, ImU32 col, float rot = 0.0f, int num_segments = 0) { AddEllipseFilled(center, ImVec2(radius_x, radius_y), col, rot, num_segments); }                        // OBSOLETED in 1.90.5 (Mar 2024)
     //inline  void  PathEllipticalArcTo(const ImVec2& center, float radius_x, float radius_y, float rot, float a_min, float a_max, int num_segments = 0) { PathEllipticalArcTo(center, ImVec2(radius_x, radius_y), rot, a_min, a_max, num_segments); } // OBSOLETED in 1.90.5 (Mar 2024)
-    //inline  void  AddBezierCurve(const ImVec2& p1, const ImVec2& p2, const ImVec2& p3, const ImVec2& p4, ImU32 col, float thickness, int num_segments = 0) { AddBezierCubic(p1, p2, p3, p4, col, thickness, num_segments); } // OBSOLETED in 1.80 (Jan 2021)
+    //inline  void  AddBezierCurve(const ImVec2& p1, const ImVec2& p2, const ImVec2& p3, const ImVec2& p4, ImU32 col, float thickness, int num_segments = 0) { AddBezierCubic(p1, p2, p3, p4, col, thickness, num_segments); }                         // OBSOLETED in 1.80 (Jan 2021)
-    //inline  void  PathBezierCurveTo(const ImVec2& p2, const ImVec2& p3, const ImVec2& p4, int num_segments = 0) { PathBezierCubicCurveTo(p2, p3, p4, num_segments); } // OBSOLETED in 1.80 (Jan 2021)
+    //inline  void  PathBezierCurveTo(const ImVec2& p2, const ImVec2& p3, const ImVec2& p4, int num_segments = 0) { PathBezierCubicCurveTo(p2, p3, p4, num_segments); }                                                                                // OBSOLETED in 1.80 (Jan 2021)
 
     // [Internal helpers]
     IMGUI_API void  _ResetForNewFrame();

imgui_demo.cpp

@@ -2265,7 +2265,10 @@ static void ShowDemoWindowWidgets(ImGuiDemoWindowData* demo_data)
         // Demonstrate using advanced flags for DragXXX and SliderXXX functions. Note that the flags are the same!
         static ImGuiSliderFlags flags = ImGuiSliderFlags_None;
         ImGui::CheckboxFlags("ImGuiSliderFlags_AlwaysClamp", &flags, ImGuiSliderFlags_AlwaysClamp);
-        ImGui::SameLine(); HelpMarker("Always clamp value to min/max bounds (if any) when input manually with CTRL+Click.");
+        ImGui::CheckboxFlags("ImGuiSliderFlags_ClampOnInput", &flags, ImGuiSliderFlags_ClampOnInput);
+        ImGui::SameLine(); HelpMarker("Clamp value to min/max bounds when input manually with CTRL+Click. By default CTRL+Click allows going out of bounds.");
+        ImGui::CheckboxFlags("ImGuiSliderFlags_ClampZeroRange", &flags, ImGuiSliderFlags_ClampZeroRange);
+        ImGui::SameLine(); HelpMarker("Clamp even if min==max==0.0f. Otherwise DragXXX functions don't clamp.");
         ImGui::CheckboxFlags("ImGuiSliderFlags_Logarithmic", &flags, ImGuiSliderFlags_Logarithmic);
         ImGui::SameLine(); HelpMarker("Enable logarithmic editing (more precision for small values).");
         ImGui::CheckboxFlags("ImGuiSliderFlags_NoRoundToFormat", &flags, ImGuiSliderFlags_NoRoundToFormat);
@@ -2283,6 +2286,8 @@ static void ShowDemoWindowWidgets(ImGuiDemoWindowData* demo_data)
         ImGui::DragFloat("DragFloat (0 -> +inf)", &drag_f, 0.005f, 0.0f, FLT_MAX, "%.3f", flags);
         ImGui::DragFloat("DragFloat (-inf -> 1)", &drag_f, 0.005f, -FLT_MAX, 1.0f, "%.3f", flags);
         ImGui::DragFloat("DragFloat (-inf -> +inf)", &drag_f, 0.005f, -FLT_MAX, +FLT_MAX, "%.3f", flags);
+        //ImGui::DragFloat("DragFloat (0 -> 0)", &drag_f, 0.005f, 0.0f, 0.0f, "%.3f", flags);           // To test ClampZeroRange
+        //ImGui::DragFloat("DragFloat (100 -> 100)", &drag_f, 0.005f, 100.0f, 100.0f, "%.3f", flags);
         ImGui::DragInt("DragInt (0 -> 100)", &drag_i, 0.5f, 0, 100, "%d", flags);
 
         // Sliders

imgui_internal.h

@@ -3402,6 +3402,7 @@ namespace ImGui
     IMGUI_API bool          DataTypeApplyFromText(const char* buf, ImGuiDataType data_type, void* p_data, const char* format, void* p_data_when_empty = NULL);
     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_API bool          DataTypeIsZero(ImGuiDataType data_type, const void* p_data);
 
     // InputText
     IMGUI_API bool          InputTextEx(const char* label, const char* hint, char* buf, int buf_size, const ImVec2& size_arg, ImGuiInputTextFlags flags, ImGuiInputTextCallback callback = NULL, void* user_data = NULL);

imgui_widgets.cpp

@@ -2351,6 +2351,12 @@ bool ImGui::DataTypeClamp(ImGuiDataType data_type, void* p_data, const void* p_m
     return false;
 }
 
+bool ImGui::DataTypeIsZero(ImGuiDataType data_type, const void* p_data)
+{
+    ImGuiContext& g = *GImGui;
+    return DataTypeCompare(data_type, p_data, &g.DataTypeZeroValue) == 0;
+}
+
 static float GetMinimumStepAtDecimalPrecision(int decimal_precision)
 {
     static const float min_steps[10] = { 1.0f, 0.1f, 0.01f, 0.001f, 0.0001f, 0.00001f, 0.000001f, 0.0000001f, 0.00000001f, 0.000000001f };
@@ -2409,7 +2415,7 @@ bool ImGui::DragBehaviorT(ImGuiDataType data_type, TYPE* v, float v_speed, const
 {
     ImGuiContext& g = *GImGui;
     const ImGuiAxis axis = (flags & ImGuiSliderFlags_Vertical) ? ImGuiAxis_Y : ImGuiAxis_X;
-    const bool is_bounded = (v_min < v_max);
+    const bool is_bounded = (v_min < v_max) || ((v_min == v_max) && (v_min != 0.0f || (flags & ImGuiSliderFlags_ClampZeroRange)));
     const bool is_wrapped = is_bounded && (flags & ImGuiSliderFlags_WrapAround);
     const bool is_logarithmic = (flags & ImGuiSliderFlags_Logarithmic) != 0;
     const bool is_floating_point = (data_type == ImGuiDataType_Float) || (data_type == ImGuiDataType_Double);
@@ -2632,9 +2638,17 @@ bool ImGui::DragScalar(const char* label, ImGuiDataType data_type, void* p_data,
 
     if (temp_input_is_active)
     {
-        // Only clamp CTRL+Click input when ImGuiSliderFlags_AlwaysClamp is set
+        // Only clamp CTRL+Click input when ImGuiSliderFlags_ClampOnInput is set (generally via ImGuiSliderFlags_AlwaysClamp)
-        const bool is_clamp_input = (flags & ImGuiSliderFlags_AlwaysClamp) != 0 && (p_min == NULL || p_max == NULL || DataTypeCompare(data_type, p_min, p_max) < 0);
+        bool clamp_enabled = false;
-        return TempInputScalar(frame_bb, id, label, data_type, p_data, format, is_clamp_input ? p_min : NULL, is_clamp_input ? p_max : NULL);
+        if ((flags & ImGuiSliderFlags_ClampOnInput) && (p_min != NULL || p_max != NULL))
+        {
+            const int clamp_range_dir = (p_min != NULL && p_max != NULL) ? DataTypeCompare(data_type, p_min, p_max) : 0; // -1 when *p_min < *p_max, == 0 when *p_min == *p_max
+            if (p_min == NULL || p_max == NULL || clamp_range_dir < 0)
+                clamp_enabled = true;
+            else if ((p_min != NULL && p_max != NULL) && clamp_range_dir == 0)
+                clamp_enabled = DataTypeIsZero(data_type, p_min) ? ((flags & ImGuiSliderFlags_ClampZeroRange) != 0) : true;
+        }
+        return TempInputScalar(frame_bb, id, label, data_type, p_data, format, clamp_enabled ? p_min : NULL, clamp_enabled ? p_max : NULL);
     }
 
     // Draw frame
@@ -3214,9 +3228,9 @@ bool ImGui::SliderScalar(const char* label, ImGuiDataType data_type, void* p_dat
 
     if (temp_input_is_active)
     {
-        // Only clamp CTRL+Click input when ImGuiSliderFlags_AlwaysClamp is set
+        // Only clamp CTRL+Click input when ImGuiSliderFlags_ClampOnInput is set (generally via ImGuiSliderFlags_AlwaysClamp)
-        const bool is_clamp_input = (flags & ImGuiSliderFlags_AlwaysClamp) != 0;
+        const bool clamp_enabled = (flags & ImGuiSliderFlags_ClampOnInput) != 0;
-        return TempInputScalar(frame_bb, id, label, data_type, p_data, format, is_clamp_input ? p_min : NULL, is_clamp_input ? p_max : NULL);
+        return TempInputScalar(frame_bb, id, label, data_type, p_data, format, clamp_enabled ? p_min : NULL, clamp_enabled ? p_max : NULL);
     }
 
     // Draw frame