Added PixelCenterOffset for OpenGL/DirectX compatibility.

examples/directx9_example/main.cpp

@@ -293,6 +293,7 @@ void InitImGui()
 	io.KeyMap[ImGuiKey_X] = 'X';
 	io.KeyMap[ImGuiKey_Y] = 'Y';
 	io.KeyMap[ImGuiKey_Z] = 'Z';
+	io.PixelCenterOffset = 0.0f;
 
 	io.RenderDrawListsFn = ImImpl_RenderDrawLists;
 	io.SetClipboardTextFn = ImImpl_SetClipboardTextFn;

examples/opengl_example/main.cpp

@@ -297,6 +297,7 @@ void InitImGui()
 	io.KeyMap[ImGuiKey_X] = GLFW_KEY_X;
 	io.KeyMap[ImGuiKey_Y] = GLFW_KEY_Y;
 	io.KeyMap[ImGuiKey_Z] = GLFW_KEY_Z;
+	io.PixelCenterOffset = 0.5f;
 
 	io.RenderDrawListsFn = ImImpl_RenderDrawLists;
 	io.SetClipboardTextFn = ImImpl_SetClipboardTextFn;

imgui.cpp

@@ -262,6 +262,7 @@ ImGuiIO::ImGuiIO()
 	LogFilename = "imgui_log.txt";
 	Font = NULL;
 	FontAllowScaling = false;
+	PixelCenterOffset = 0.5f;
 	MousePos = ImVec2(-1,-1);
 	MousePosPrev = ImVec2(-1,-1);
 	MouseDoubleClickTime = 0.30f;
@@ -5003,6 +5004,8 @@ void ImBitmapFont::RenderText(float size, ImVec2 pos, ImU32 col, const ImVec4& c
 	float line_width = 0.0f;
 	const ImVec4 clip_rect = clip_rect_ref;
 
+	const float uv_offset = GImGui.IO.PixelCenterOffset;
+
 	float x = pos.x;
 	float y = pos.y;
 	for (const char* s = text_begin; s < text_end; s++)
@@ -5039,10 +5042,10 @@ void ImBitmapFont::RenderText(float size, ImVec2 pos, ImU32 col, const ImVec4& c
 					continue;
 				}
 
-				const float s1 = (0.0f + glyph->X) * tex_scale_x;
-				const float t1 = (0.0f + glyph->Y) * tex_scale_y;
-				const float s2 = (0.0f + glyph->X + glyph->Width) * tex_scale_x;
-				const float t2 = (0.0f + glyph->Y + glyph->Height) * tex_scale_y;
+				const float s1 = (uv_offset + glyph->X) * tex_scale_x;
+				const float t1 = (uv_offset + glyph->Y) * tex_scale_y;
+				const float s2 = (uv_offset + glyph->X + glyph->Width) * tex_scale_x;
+				const float t2 = (uv_offset + glyph->Y + glyph->Height) * tex_scale_y;
 
 				out_vertices[0].pos = ImVec2(x1, y1);
 				out_vertices[0].uv  = ImVec2(s1, t1);

imgui.h

@@ -373,6 +373,7 @@ struct ImGuiIO
 	ImFont		Font;						// <auto>					// Gets passed to text functions. Typedef ImFont to the type you want (ImBitmapFont* or your own font).
 	float		FontHeight;					// <auto>					// Default font height, must be the vertical distance between two lines of text, aka == CalcTextSize(" ").y
 	bool		FontAllowScaling;			// = false					// Set to allow scaling text with CTRL+Wheel.
+	float		PixelCenterOffset;			// = 0.5f					// Set to 0.0f for DirectX <= 9, 0.5f for Direct3D >= 10 and OpenGL.
 
 	// Settings - Functions (fill once)
 	void		(*RenderDrawListsFn)(ImDrawList** const draw_lists, int count);	// Required