Arranged things better, made API consistent, cleaned up code

README.md

@@ -2,3 +2,6 @@ imgui-backends
 ==============
 
 Windowing/rendering backends for https://github.com/ocornut/imgui
+
+Currently supported:
+ - SFML

SFML/imgui-SFML.h

@@ -0,0 +1,150 @@
+#include <vector>
+#include <SFML/Window/Keyboard.hpp>
+#include <SFML/Window/Event.hpp>
+#include <SFML/Graphics/Texture.hpp>
+#include <SFML/Graphics/Vertex.hpp>
+#include <SFML/Graphics/RenderWindow.hpp>
+
+namespace ImGui
+{
+    namespace ImImpl
+    {
+        static sf::Clock ImImpl_timeElapsed;
+        static bool ImImpl_mousePressed[2] = { false, false };
+        static sf::RenderWindow* ImImpl_window;
+        static sf::Texture ImImpl_fontTex;
+        static void ImImpl_RenderDrawLists(ImDrawList** const cmd_lists, int cmd_lists_count);
+    }
+    namespace SFML
+    {
+        static void SetWindow(sf::RenderWindow& window){ImImpl::ImImpl_window=&window;}
+        static void ProcessEvent(sf::Event &event)
+        {
+            switch(event.type)
+            {
+                case sf::Event::MouseButtonPressed:
+                {
+                    ImImpl::ImImpl_mousePressed[event.mouseButton.button]=true;
+                    break;
+                }
+                case sf::Event::MouseButtonReleased:
+                {
+                    ImImpl::ImImpl_mousePressed[event.mouseButton.button]=false;
+                    break;
+                }
+                case sf::Event::MouseWheelMoved:
+                {
+                    ImGuiIO& io = ImGui::GetIO();
+                    io.MouseWheel += (float)event.mouseWheel.delta;
+                    break;
+                }
+                case sf::Event::KeyPressed:
+                {
+                    ImGuiIO& io = ImGui::GetIO();
+                    io.KeysDown[event.key.code]=true;
+                    io.KeyCtrl=event.key.control;
+                    io.KeyShift=event.key.shift;
+                    break;
+                }
+                case sf::Event::KeyReleased:
+                {
+                    ImGuiIO& io = ImGui::GetIO();
+                    io.KeysDown[event.key.code]=false;
+                    io.KeyCtrl=event.key.control;
+                    io.KeyShift=event.key.shift;
+                    break;
+                }
+                case sf::Event::TextEntered:
+                {
+                    if(event.text.unicode > 0 && event.text.unicode < 0x10000)
+                        ImGui::GetIO().AddInputCharacter(event.text.unicode);
+                    break;
+                }
+                default: break;
+            }
+        }
+
+        static void InitImGui()
+        {
+            ImGuiIO& io = ImGui::GetIO();
+            io.PixelCenterOffset = 0.0f;
+            io.KeyMap[ImGuiKey_Tab] = sf::Keyboard::Tab;
+            io.KeyMap[ImGuiKey_LeftArrow] = sf::Keyboard::Left;
+            io.KeyMap[ImGuiKey_RightArrow] = sf::Keyboard::Right;
+            io.KeyMap[ImGuiKey_UpArrow] = sf::Keyboard::Up;
+            io.KeyMap[ImGuiKey_DownArrow] = sf::Keyboard::Down;
+            io.KeyMap[ImGuiKey_Home] = sf::Keyboard::Home;
+            io.KeyMap[ImGuiKey_End] = sf::Keyboard::End;
+            io.KeyMap[ImGuiKey_Delete] = sf::Keyboard::Delete;
+            io.KeyMap[ImGuiKey_Backspace] = sf::Keyboard::BackSpace;
+            io.KeyMap[ImGuiKey_Enter] = sf::Keyboard::Return;
+            io.KeyMap[ImGuiKey_Escape] = sf::Keyboard::Escape;
+            io.KeyMap[ImGuiKey_A] = sf::Keyboard::A;
+            io.KeyMap[ImGuiKey_C] = sf::Keyboard::C;
+            io.KeyMap[ImGuiKey_V] = sf::Keyboard::V;
+            io.KeyMap[ImGuiKey_X] = sf::Keyboard::X;
+            io.KeyMap[ImGuiKey_Y] = sf::Keyboard::Y;
+            io.KeyMap[ImGuiKey_Z] = sf::Keyboard::Z;
+
+            io.RenderDrawListsFn = ImImpl::ImImpl_RenderDrawLists;
+
+            // Load font texture
+            const void* png_data;
+            unsigned int png_size;
+            ImGui::GetDefaultFontData(NULL, NULL, &png_data, &png_size);
+            ImImpl::ImImpl_fontTex.loadFromMemory(png_data, png_size);
+            ImImpl::ImImpl_timeElapsed.restart();
+        }
+
+        static void UpdateImGui(sf::Window &window)
+        {
+            ImGuiIO& io = ImGui::GetIO();
+            int w, h;
+            sf::Vector2u size = window.getSize();
+            w=size.x; h=size.y;
+            io.DisplaySize = ImVec2((float)w, (float)h);
+            static double time = 0.0f;
+            const double current_time = ImImpl::ImImpl_timeElapsed.getElapsedTime().asSeconds();
+            io.DeltaTime = (float)(current_time - time);
+            time = current_time;
+            sf::Vector2i mouse = sf::Mouse::getPosition(window);
+            io.MousePos = ImVec2((float)mouse.x, (float)mouse.y);
+            io.MouseDown[0] = ImImpl::ImImpl_mousePressed[0] || sf::Mouse::isButtonPressed(sf::Mouse::Left);
+            io.MouseDown[1] = ImImpl::ImImpl_mousePressed[1] || sf::Mouse::isButtonPressed(sf::Mouse::Right);
+            ImGui::NewFrame();
+        }
+    }
+
+    namespace ImImpl
+    {
+        static void ImImpl_RenderDrawLists(ImDrawList** const cmd_lists, int cmd_lists_count)
+        {
+            if (cmd_lists_count == 0)
+                return;
+
+            sf::RenderStates states(&ImImpl::ImImpl_fontTex);
+            states.blendMode = sf::BlendMode(sf::BlendMode::SrcAlpha, sf::BlendMode::OneMinusSrcAlpha);
+
+            for (int n = 0; n < cmd_lists_count; n++)
+            {
+                const ImDrawList* cmd_list = cmd_lists[n];
+                const unsigned char* vtx_buffer_ = (const unsigned char*)(&(cmd_list->vtx_buffer.front()));
+                sf::Vertex* vtx_buffer = (sf::Vertex*)vtx_buffer_;
+                int i=cmd_list->vtx_buffer.size()-1;
+                while(i>=0)
+                {
+                    vtx_buffer[i].texCoords.x*=ImImpl::ImImpl_fontTex.getSize().x;
+                    vtx_buffer[i].texCoords.y*=ImImpl::ImImpl_fontTex.getSize().y;
+                    --i;
+                }
+                int vtx_offset = 0;
+                for (size_t cmd_i = 0; cmd_i < cmd_list->commands.size(); cmd_i++)
+                {
+                    const ImDrawCmd* pcmd = &cmd_list->commands.at(cmd_i);
+                    ImImpl::ImImpl_window->draw(&vtx_buffer[vtx_offset], pcmd->vtx_count, sf::Triangles, states);
+                    vtx_offset += pcmd->vtx_count;
+                }
+            }
+        }
+    }
+}