/* * Copyright 2017 Google Inc. * * Use of this source code is governed by a BSD-style license that can be * found in the LICENSE file. */ #ifndef ImGuiLayer_DEFINED #define ImGuiLayer_DEFINED #include "include/core/SkPaint.h" #include "include/private/SkTArray.h" #include "tools/sk_app/Window.h" #include "imgui.h" namespace ImGui { // Helper object for drawing in a widget region, with draggable points struct DragCanvas { DragCanvas(const void* id, SkPoint tl = { 0.0f, 0.0f }, SkPoint br = { 1.0f, 1.0f }, float aspect = -1.0f) : fID(0), fDragging(false) { ImGui::PushID(id); fDrawList = ImGui::GetWindowDrawList(); // Logical size SkScalar w = SkTAbs(br.fX - tl.fX), h = SkTAbs(br.fY - tl.fY); // Determine aspect ratio automatically by default if (aspect < 0) { aspect = h / w; } float availWidth = SkTMax(ImGui::GetContentRegionAvailWidth(), 1.0f); fPos = ImGui::GetCursorScreenPos(); fSize = ImVec2(availWidth, availWidth * aspect); SkPoint local[4] = { { tl.fX, tl.fY }, { br.fX, tl.fY }, { tl.fX, br.fY }, { br.fX, br.fY }, }; SkPoint screen[4] = { { fPos.x , fPos.y }, { fPos.x + fSize.x, fPos.y }, { fPos.x , fPos.y + fSize.y }, { fPos.x + fSize.x, fPos.y + fSize.y }, }; fLocalToScreen.setPolyToPoly(local, screen, 4); fScreenToLocal.setPolyToPoly(screen, local, 4); } ~DragCanvas() { ImGui::SetCursorScreenPos(ImVec2(fPos.x, fPos.y + fSize.y)); ImGui::Spacing(); ImGui::PopID(); } void fillColor(ImU32 color) { fDrawList->AddRectFilled(fPos, ImVec2(fPos.x + fSize.x, fPos.y + fSize.y), color); } void dragPoint(SkPoint* p, bool tooltip = false, ImU32 color = 0xFFFFFFFF) { // Transform points from logical coordinates to screen coordinates SkPoint center = fLocalToScreen.mapXY(p->fX, p->fY); // Invisible 10x10 button ImGui::PushID(fID++); ImGui::SetCursorScreenPos(ImVec2(center.fX - 5, center.fY - 5)); ImGui::InvisibleButton("", ImVec2(10, 10)); if (ImGui::IsItemActive() && ImGui::IsMouseDragging()) { // Update screen position to track mouse, clamped to our area ImGuiIO& io = ImGui::GetIO(); center.set(SkTPin(io.MousePos.x, fPos.x, fPos.x + fSize.x), SkTPin(io.MousePos.y, fPos.y, fPos.y + fSize.y)); // Update local coordinates for the caller *p = fScreenToLocal.mapXY(center.fX, center.fY); fDragging = true; } if (tooltip && ImGui::IsItemHovered()) { ImGui::SetTooltip("x: %.3f\ny: %.3f", p->fX, p->fY); } ImGui::PopID(); fScreenPoints.push_back(ImVec2(center.fX, center.fY)); fDrawList->AddCircle(fScreenPoints.back(), 5.0f, color); } ImDrawList* fDrawList; // Location and dimensions (in screen coordinates) ImVec2 fPos; ImVec2 fSize; // Screen coordinates of points (for additional user drawing) SkSTArray<4, ImVec2, true> fScreenPoints; // To simplify dragPoint SkMatrix fLocalToScreen; SkMatrix fScreenToLocal; int fID; bool fDragging; }; } class ImGuiLayer : public sk_app::Window::Layer { public: ImGuiLayer(); ~ImGuiLayer() override; typedef std::function SkiaWidgetFunc; void skiaWidget(const ImVec2& size, SkiaWidgetFunc func); void onAttach(sk_app::Window* window) override; void onPrePaint() override; void onPaint(SkSurface*) override; bool onMouse(int x, int y, InputState state, ModifierKey modifiers) override; bool onMouseWheel(float delta, ModifierKey modifiers) override; bool onKey(sk_app::Window::Key key, InputState state, ModifierKey modifiers) override; bool onChar(SkUnichar c, ModifierKey modifiers) override; private: sk_app::Window* fWindow; SkPaint fFontPaint; SkTArray fSkiaWidgetFuncs; }; #endif