Moved IM_NEW, IM_DELETE helpers to imgui.h for convenient use by back-ends and user code.

This commit is contained in:
omar 2018-03-13 16:14:50 +01:00
parent 7b833dabc8
commit 0e3a6ef4f7
2 changed files with 10 additions and 9 deletions

10
imgui.h
View File

@ -1177,6 +1177,16 @@ public:
inline bool contains(const value_type& v) const { const T* data = Data; const T* data_end = Data + Size; while (data < data_end) if (*data++ == v) return true; return false; }
};
// Helper: IM_NEW(), IM_PLACEMENT_NEW(), IM_DELETE() macros to call MemAlloc + Placement New, Placement Delete + MemFree
// We call C++ constructor on own allocated memory via the placement "new(ptr) Type()" syntax.
// Defining a custom placement new() with a dummy parameter allows us to bypass including <new> which on some platforms complains when user has disabled exceptions.
struct ImNewDummy {};
inline void* operator new(size_t, ImNewDummy, void* ptr) { return ptr; }
inline void operator delete(void*, ImNewDummy, void*) {} // This is only required so we can use the symetrical new()
#define IM_PLACEMENT_NEW(_PTR) new(ImNewDummy(), _PTR)
#define IM_NEW(_TYPE) new(ImNewDummy(), ImGui::MemAlloc(sizeof(_TYPE))) _TYPE
template<typename T> void IM_DELETE(T*& p) { if (p) { p->~T(); ImGui::MemFree(p); p = NULL; } }
// Helper: execute a block of code at maximum once a frame. Convenient if you want to quickly create an UI within deep-nested code that runs multiple times every frame.
// Usage: static ImGuiOnceUponAFrame oaf; if (oaf) ImGui::Text("This will be called only once per frame");
struct ImGuiOnceUponAFrame

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@ -165,15 +165,6 @@ static inline ImVec2 ImRotate(const ImVec2& v, float cos_a, float sin_a)
static inline float ImLinearSweep(float current, float target, float speed) { if (current < target) return ImMin(current + speed, target); if (current > target) return ImMax(current - speed, target); return current; }
static inline ImVec2 ImMul(const ImVec2& lhs, const ImVec2& rhs) { return ImVec2(lhs.x * rhs.x, lhs.y * rhs.y); }
// We call C++ constructor on own allocated memory via the placement "new(ptr) Type()" syntax.
// Defining a custom placement new() with a dummy parameter allows us to bypass including <new> which on some platforms complains when user has disabled exceptions.
struct ImNewPlacementDummy {};
inline void* operator new(size_t, ImNewPlacementDummy, void* ptr) { return ptr; }
inline void operator delete(void*, ImNewPlacementDummy, void*) {} // This is only required so we can use the symetrical new()
#define IM_PLACEMENT_NEW(_PTR) new(ImNewPlacementDummy(), _PTR)
#define IM_NEW(_TYPE) new(ImNewPlacementDummy(), ImGui::MemAlloc(sizeof(_TYPE))) _TYPE
template <typename T> void IM_DELETE(T*& p) { if (p) { p->~T(); ImGui::MemFree(p); p = NULL; } }
//-----------------------------------------------------------------------------
// Types
//-----------------------------------------------------------------------------