Fixed ImGuiTextFilter triming of leading/trailing blanks. Documented "Filtering" section of demo better.

imgui.cpp

@@ -725,6 +725,7 @@ static void RegisterAliveId(const ImGuiID& id)
 
 //-----------------------------------------------------------------------------
 
+// Helper: Key->value storage
 void ImGuiStorage::Clear()
 {
     Data.clear();
@@ -797,6 +798,7 @@ void ImGuiStorage::SetAllInt(int v)
 
 //-----------------------------------------------------------------------------
 
+// Helper: Parse and apply text filters. In format "aaaaa[,bbbb][,ccccc]"
 ImGuiTextFilter::ImGuiTextFilter()
 {
     InputBuf[0] = 0;
@@ -888,6 +890,7 @@ bool ImGuiTextFilter::PassFilter(const char* val) const
 
 //-----------------------------------------------------------------------------
 
+// Helper: Text buffer for logging/accumulating text
 void ImGuiTextBuffer::append(const char* fmt, ...)
 {
     va_list args;
@@ -5854,6 +5857,11 @@ void ShowTestWindow(bool* open)
     if (ImGui::CollapsingHeader("Filtering"))
     {
         static ImGuiTextFilter filter;
+		ImGui::Text("Filter usage:\n"
+			        "  \"\"         display all lines\n"
+			        "  \"xxx\"      display lines containing \"xxx\"\n"
+					"  \"xxx,yyy\"  display lines containing \"xxx\" or \"yyy\"\n"
+					"  \"-xxx\"     hide lines containing \"xxx\"");
 		filter.Draw();
         const char* lines[] = { "aaa1.c", "bbb1.c", "ccc1.c", "aaa2.cpp", "bbb2.cpp", "ccc2.cpp", "abc.h", "hello, world" };
         for (size_t i = 0; i < IM_ARRAYSIZE(lines); i++)

imgui.h

@@ -107,7 +107,7 @@ public:
 
 // Helpers at bottom of the file:
 // - if (IMGUI_ONCE_UPON_A_FRAME)       // Execute a block of code once per frame only
-// - struct ImGuiTextFilter             // Parse and apply text filter. In format "aaaaa[,bbbb][,ccccc]"
+// - struct ImGuiTextFilter             // Parse and apply text filters. In format "aaaaa[,bbbb][,ccccc]"
 // - struct ImGuiTextBuffer             // Text buffer for logging/accumulating text
 // - struct ImGuiStorage                // Custom key value storage (if you need to alter open/close states manually)
 // - struct ImDrawList                  // Draw command list
@@ -449,7 +449,7 @@ private:
     bool        TryIsNewFrame() const   { const int current_frame = ImGui::GetFrameCount(); if (LastFrame == current_frame) return false; LastFrame = current_frame; return true; }
 };
 
-// Helper: Parse and apply text filter. In format "aaaaa[,bbbb][,ccccc]"
+// Helper: Parse and apply text filters. In format "aaaaa[,bbbb][,ccccc]"
 struct ImGuiTextFilter
 {
     struct TextRange 
@@ -463,7 +463,7 @@ struct ImGuiTextFilter
         const char* end() const { return e; }
         bool empty() const { return b == e; }
         char front() const { return *b; }
-        static bool isblank(char c) { return c == ' ' && c == '\t'; } 
+        static bool isblank(char c) { return c == ' ' || c == '\t'; } 
         void trim_blanks() { while (b < e && isblank(*b)) b++; while (e > b && isblank(*(e-1))) e--; }
         void split(char separator, ImVector<TextRange>& out);
     };