Internals: refactor RenderRectFilledRangeH() into RenderRectFilledInRangeH() to take absolute coordinates instead of normalized ones.

Amend 01d4bf299a (#1296)

imgui.h

@@ -1927,7 +1927,7 @@ enum ImGuiSliderFlags_
     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_NoSpeedTweaks      = 1 << 11,      // Disable keyboard modifiers altering tweak speed. Useful if you want to alter tweak speed yourself based on your own logic.
     ImGuiSliderFlags_AlwaysClamp        = ImGuiSliderFlags_ClampOnInput | ImGuiSliderFlags_ClampZeroRange,
-    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_InvalidMask_       = 0x7000000F,   // [Internal] We treat using those bits as being potentially a 'float power' argument from legacy API (obsoleted 2020-08) that has got miscast to this enum, and will trigger an assert if needed.
 };
 
 // Identify a mouse button.

imgui_demo.cpp

@@ -2045,10 +2045,12 @@ static void DemoWindowWidgetsProgressBars()
     if (ImGui::TreeNode("Progress Bars"))
     {
         // Animate a simple progress bar
-        static float progress = 0.0f, progress_dir = 1.0f;
+        static float progress_accum = 0.0f, progress_dir = 1.0f;
-        progress += progress_dir * 0.4f * ImGui::GetIO().DeltaTime;
+        progress_accum += progress_dir * 0.4f * ImGui::GetIO().DeltaTime;
-        if (progress >= +1.1f) { progress = +1.1f; progress_dir *= -1.0f; }
+        if (progress_accum >= +1.1f) { progress_accum = +1.1f; progress_dir *= -1.0f; }
-        if (progress <= -0.1f) { progress = -0.1f; progress_dir *= -1.0f; }
+        if (progress_accum <= -0.1f) { progress_accum = -0.1f; progress_dir *= -1.0f; }
+
+        const float progress = IM_CLAMP(progress_accum, 0.0f, 1.0f);
 
         // Typically we would use ImVec2(-1.0f,0.0f) or ImVec2(-FLT_MIN,0.0f) to use all available width,
         // or ImVec2(width,0.0f) for a specified width. ImVec2(0.0f,0.0f) uses ItemWidth.
@@ -2056,9 +2058,8 @@ static void DemoWindowWidgetsProgressBars()
         ImGui::SameLine(0.0f, ImGui::GetStyle().ItemInnerSpacing.x);
         ImGui::Text("Progress Bar");
 
-        float progress_saturated = IM_CLAMP(progress, 0.0f, 1.0f);
         char buf[32];
-        sprintf(buf, "%d/%d", (int)(progress_saturated * 1753), 1753);
+        sprintf(buf, "%d/%d", (int)(progress * 1753), 1753);
         ImGui::ProgressBar(progress, ImVec2(0.f, 0.f), buf);
 
         // Pass an animated negative value, e.g. -1.0f * (float)ImGui::GetTime() is the recommended value.

imgui_draw.cpp

@@ -5830,7 +5830,7 @@ begin:
 // - RenderBullet()
 // - RenderCheckMark()
 // - RenderArrowPointingAt()
-// - RenderRectFilledRangeH()
+// - RenderRectFilledInRangeH()
 // - RenderRectFilledWithHole()
 //-----------------------------------------------------------------------------
 // Function in need of a redesign (legacy mess)
@@ -5913,15 +5913,15 @@ static inline float ImAcos01(float x)
 }
 
 // FIXME: Cleanup and move code to ImDrawList.
-void ImGui::RenderRectFilledRangeH(ImDrawList* draw_list, const ImRect& rect, ImU32 col, float x_start_norm, float x_end_norm, float rounding)
+// - Before 2025-12-04: RenderRectFilledRangeH()   with 'float x_start_norm, float x_end_norm` <- normalized
+// - After  2025-12-04: RenderRectFilledInRangeH() with 'float x1, float x2'                   <- absolute coords!!
+void ImGui::RenderRectFilledInRangeH(ImDrawList* draw_list, const ImRect& rect, ImU32 col, float x1, float x2, float rounding)
 {
-    if (x_end_norm == x_start_norm)
+    if (x1 == x2)
         return;
-    if (x_start_norm > x_end_norm)
-        ImSwap(x_start_norm, x_end_norm);
 
-    ImVec2 p0 = ImVec2(ImLerp(rect.Min.x, rect.Max.x, x_start_norm), rect.Min.y);
+    ImVec2 p0 = ImVec2(x1, rect.Min.y);
-    ImVec2 p1 = ImVec2(ImLerp(rect.Min.x, rect.Max.x, x_end_norm), rect.Max.y);
+    ImVec2 p1 = ImVec2(x2, rect.Max.y);
     if (rounding == 0.0f)
     {
         draw_list->AddRectFilled(p0, p1, col, 0.0f);

imgui_internal.h

@@ -3587,7 +3587,7 @@ namespace ImGui
     IMGUI_API void          RenderBullet(ImDrawList* draw_list, ImVec2 pos, ImU32 col);
     IMGUI_API void          RenderCheckMark(ImDrawList* draw_list, ImVec2 pos, ImU32 col, float sz);
     IMGUI_API void          RenderArrowPointingAt(ImDrawList* draw_list, ImVec2 pos, ImVec2 half_sz, ImGuiDir direction, ImU32 col);
-    IMGUI_API void          RenderRectFilledRangeH(ImDrawList* draw_list, const ImRect& rect, ImU32 col, float x_start_norm, float x_end_norm, float rounding);
+    IMGUI_API void          RenderRectFilledInRangeH(ImDrawList* draw_list, const ImRect& rect, ImU32 col, float x1, float x2, float rounding);
     IMGUI_API void          RenderRectFilledWithHole(ImDrawList* draw_list, const ImRect& outer, const ImRect& inner, ImU32 col, float rounding);
 
     // Widgets: Text

imgui_widgets.cpp

@@ -1440,7 +1440,10 @@ void ImGui::ProgressBar(float fraction, const ImVec2& size_arg, const char* over
     // Render
     RenderFrame(bb.Min, bb.Max, GetColorU32(ImGuiCol_FrameBg), true, style.FrameRounding);
     bb.Expand(ImVec2(-style.FrameBorderSize, -style.FrameBorderSize));
-    RenderRectFilledRangeH(window->DrawList, bb, GetColorU32(ImGuiCol_PlotHistogram), fill_n0, fill_n1, style.FrameRounding);
+    float fill_x0 = ImLerp(bb.Min.x, bb.Max.x, fill_n0);
+    float fill_x1 = ImLerp(bb.Min.x, bb.Max.x, fill_n1);
+    if (fill_x0 < fill_x1)
+        RenderRectFilledInRangeH(window->DrawList, bb, GetColorU32(ImGuiCol_PlotHistogram), fill_x0, fill_x1, style.FrameRounding);
 
     // Default displaying the fraction as percentage string, but user can override it
     // Don't display text for indeterminate bars by default
@@ -1456,7 +1459,7 @@ void ImGui::ProgressBar(float fraction, const ImVec2& size_arg, const char* over
         ImVec2 overlay_size = CalcTextSize(overlay, NULL);
         if (overlay_size.x > 0.0f)
         {
-            float text_x = is_indeterminate ? (bb.Min.x + bb.Max.x - overlay_size.x) * 0.5f : ImLerp(bb.Min.x, bb.Max.x, fill_n1) + style.ItemSpacing.x;
+            float text_x = is_indeterminate ? (bb.Min.x + bb.Max.x - overlay_size.x) * 0.5f : fill_x1 + style.ItemSpacing.x;
             RenderTextClipped(ImVec2(ImClamp(text_x, bb.Min.x, bb.Max.x - overlay_size.x - style.ItemInnerSpacing.x), bb.Min.y), bb.Max, overlay, NULL, &overlay_size, ImVec2(0.0f, 0.5f), &bb);
         }
     }