Phone: turns with the phone (portrait layout), fullscreen, picture the right way up; tap/drag fixes for touch

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NMSrd5oe1GpUD7E6d825KP

android/AndroidManifest.xml

@@ -19,7 +19,7 @@
             android:name="io.github.nexoniarz.fry3dx.FryActivity"
             android:exported="true"
             android:label="Fry3DX"
-            android:screenOrientation="sensorLandscape"
+            android:screenOrientation="fullUser"
             android:launchMode="singleInstance"
             android:windowSoftInputMode="adjustResize"
             android:configChanges="layoutDirection|locale|orientation|uiMode|screenLayout|screenSize|smallestScreenSize|keyboard|keyboardHidden|navigation">

android/java/io/github/nexoniarz/fry3dx/FryActivity.java

@@ -1,5 +1,9 @@
 package io.github.nexoniarz.fry3dx;
 
+import android.os.Build;
+import android.view.WindowInsets;
+import android.view.WindowInsetsController;
+
 import org.libsdl.app.SDLActivity;
 
 // Fry3DX's activity: SDL's, loading SDL and the app (libmain.so, whose SDL_main it runs).
@@ -8,4 +12,40 @@ public class FryActivity extends SDLActivity {
     protected String[] getLibraries() {
         return new String[] {"SDL3", "main"};
     }
+
+    // The whole screen: the status and navigation bars hidden (a swipe from the edge shows them
+    // for a moment). SDL's own way (the old system-UI flags) doesn't do it on new Androids.
+    @Override
+    protected void onResume() {
+        super.onResume();
+        hideBars();
+    }
+
+    @Override
+    public void onWindowFocusChanged(boolean hasFocus) {
+        super.onWindowFocusChanged(hasFocus);
+        if (hasFocus) hideBars();
+    }
+
+    // SDL sets the bars again (its old way) whenever the window changes: hidden again after it.
+    @Override
+    protected boolean sendCommand(int command, Object data) {
+        final boolean sent = super.sendCommand(command, data);
+        if (command == COMMAND_CHANGE_WINDOW_STYLE) getWindow().getDecorView().post(new Runnable() { // (no lambdas: built against android.jar alone)
+            @Override
+            public void run() {
+                hideBars();
+            }
+        });
+        return sent;
+    }
+
+    private void hideBars() {
+        if (Build.VERSION.SDK_INT < 30) return;
+        getWindow().setDecorFitsSystemWindows(false);
+        WindowInsetsController c = getWindow().getInsetsController();
+        if (c == null) return;
+        c.hide(WindowInsets.Type.systemBars());
+        c.setSystemBarsBehavior(WindowInsetsController.BEHAVIOR_SHOW_TRANSIENT_BARS_BY_SWIPE);
+    }
 }

engine/platform/window.cpp

@@ -40,7 +40,11 @@ bool Window::init(const char* title, int width, int height, bool opengl) {
         log::error("SDL_Init failed: {}", SDL_GetError());
         return false;
     }
-    window_ = SDL_CreateWindow(title, width, height, (opengl ? SDL_WINDOW_OPENGL : SDL_WINDOW_VULKAN) | SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIGH_PIXEL_DENSITY);
+    SDL_WindowFlags flags = (opengl ? SDL_WINDOW_OPENGL : SDL_WINDOW_VULKAN) | SDL_WINDOW_RESIZABLE | SDL_WINDOW_HIGH_PIXEL_DENSITY;
+#if defined(__ANDROID__)
+    flags |= SDL_WINDOW_FULLSCREEN; // (the whole screen: no status or navigation bar over the edges)
+#endif
+    window_ = SDL_CreateWindow(title, width, height, flags);
     if (!window_) {
         log::error("SDL_CreateWindow failed: {}", SDL_GetError());
         return false;

engine/rhi/vulkan/vk_device.cpp

@@ -227,6 +227,9 @@ bool Device::createSwapchain() {
     vkDeviceWaitIdle(device_);
     VkSwapchainKHR old = swapchain_;
     auto sc = vkb::SwapchainBuilder(physical_, device_, surface_)
+#if defined(__ANDROID__) // (the compositor turns the picture with the phone: drawn as it's seen)
+                  .set_pre_transform_flags(VK_SURFACE_TRANSFORM_IDENTITY_BIT_KHR)
+#endif
                   .set_desired_format({VK_FORMAT_B8G8R8A8_UNORM, VK_COLOR_SPACE_SRGB_NONLINEAR_KHR})
                   .set_desired_present_mode(vsync_ ? VK_PRESENT_MODE_FIFO_KHR : VK_PRESENT_MODE_MAILBOX_KHR)
                   .add_fallback_present_mode(vsync_ ? VK_PRESENT_MODE_FIFO_KHR : VK_PRESENT_MODE_IMMEDIATE_KHR)
@@ -312,6 +315,13 @@ void Device::endFrame() {
     pi.pSwapchains = &swapchain_;
     pi.pImageIndices = &imageIndex_;
     VkResult r = vkQueuePresentKHR(queue_, &pi);
+#if defined(__ANDROID__) // (suboptimal every frame while the phone's turned: the compositor turns it; only a new size matters)
+    if (r == VK_SUBOPTIMAL_KHR) {
+        uint32_t w = 0, h = 0;
+        window_->pixelSize(w, h);
+        if (w == extent_.width && h == extent_.height) r = VK_SUCCESS;
+    }
+#endif
     if (r == VK_ERROR_OUT_OF_DATE_KHR || r == VK_SUBOPTIMAL_KHR) swapchainDirty_ = true;
     else VK_CHECK(r);
 

src/app.cpp

@@ -514,6 +514,7 @@ public:
         ImGuiIO& io = ImGui::GetIO();
         if (touch()) touchFrame(io);
         const ImGuiID dock = ImGui::DockSpaceOverViewport(0, nullptr, ImGuiDockNodeFlags_PassthruCentralNode);
+        if (touch() && (io.DisplaySize.y > io.DisplaySize.x) != portrait_) portrait_ = !portrait_, layoutDone_ = false; // (the phone turned: its layout)
         if (!layoutDone_) defaultLayout(dock);
         if (ImGuiDockNode* c = ImGui::DockBuilderGetCentralNode(dock)) viewMin_ = c->Pos, viewMax_ = ImVec2(c->Pos.x + c->Size.x, c->Pos.y + c->Size.y);
         updateCamera(io);
@@ -612,7 +613,7 @@ private:
         Scene before;
         std::set<std::pair<int, int>> bevelEdges;
     } drag_;
-    bool boxing_ = false, painting_ = false, lassoing_ = false;
+    bool boxing_ = false, painting_ = false, lassoing_ = false, tapDraw_ = false;
     ImVec2 boxStart_{0, 0};
     std::vector<ImVec2> lasso_;
     std::pair<int, int> cutHover_{-1, -1};
@@ -664,7 +665,7 @@ private:
     bool pasteOnSurface_ = true;
     uint32_t renamingFolder_ = 0;
     // Touch (set when it starts: fry_touch).
-    bool touchMode_ = false, panelsOpen_ = false, viewsOpen_ = false, shiftLatch_ = false, ctrlLatch_ = false, touchOrbit_ = false;
+    bool touchMode_ = false, portrait_ = false, showToolbox_ = false, panelsOpen_ = false, viewsOpen_ = false, shiftLatch_ = false, ctrlLatch_ = false, touchOrbit_ = false;
     struct Gesture {
         bool two = false, longDone = false, rightUp = false;
         ImVec2 mid{}, downPos{};
@@ -3260,7 +3261,7 @@ private:
             const float spread = std::max(std::hypot(fingers[0].x - fingers[1].x, fingers[0].y - fingers[1].y), 1.0f);
             if (!gest_.two && !drag_.active && inView(mid) && !ImGui::IsAnyItemActive()) { // two fingers: the first's tap or drag is off
                 gest_.two = true, gest_.mid = mid, gest_.spread = spread;
-                boxing_ = lassoing_ = touchOrbit_ = false;
+                boxing_ = lassoing_ = touchOrbit_ = tapDraw_ = false;
                 io.AddMouseButtonEvent(ImGuiMouseButton_Left, false);
             }
             if (gest_.two) {
@@ -3279,7 +3280,7 @@ private:
         if (std::hypot(p.x - gest_.downPos.x, p.y - gest_.downPos.y) > 12) gest_.downAt = now() + 1e9; // (moved: not a long press)
         if (!gest_.longDone && now() - gest_.downAt > 0.55 && !drag_.active) {
             gest_.longDone = true;
-            boxing_ = lassoing_ = touchOrbit_ = false;
+            boxing_ = lassoing_ = touchOrbit_ = tapDraw_ = false;
             io.AddMouseButtonEvent(ImGuiMouseButton_Left, false);
             io.AddMouseButtonEvent(ImGuiMouseButton_Right, true);
             gest_.rightUp = true;
@@ -4133,7 +4134,8 @@ private:
             if (touchOrbit_ && moved && ImGui::IsMouseDown(ImGuiMouseButton_Left)) orbitBy(io.MouseDelta);
             if (!ImGui::IsMouseDown(ImGuiMouseButton_Left)) {
                 boxing_ = false;
-                if (std::exchange(touchOrbit_, false) && moved) return;
+                if (std::exchange(touchOrbit_, false) && moved) return void(tapDraw_ = false);
+                if (std::exchange(tapDraw_, false)) return addDrawPoint(io);
                 if (std::hypot(io.MousePos.x - boxStart_.x, io.MousePos.y - boxStart_.y) > 4) {
                     const ImVec2 a(std::min(boxStart_.x, io.MousePos.x), std::min(boxStart_.y, io.MousePos.y)), b(std::max(boxStart_.x, io.MousePos.x), std::max(boxStart_.y, io.MousePos.y));
                     regionSelect([&](ImVec2 s) { return s.x >= a.x && s.x <= b.x && s.y >= a.y && s.y <= b.y; }, io.KeyShift, io.KeyCtrl, !io.KeyShift && !io.KeyCtrl);
@@ -4159,12 +4161,9 @@ private:
         }
         if (!mouseInView(io)) return;
         if (tool_ == Tool::Draw) {
-            if (ImGui::IsMouseClicked(ImGuiMouseButton_Left))
+            if (!ImGui::IsMouseClicked(ImGuiMouseButton_Left)) return;
-                if (auto p = drawPoint(io)) {
+            if (touch()) return void((boxing_ = touchOrbit_ = tapDraw_ = true, boxStart_ = io.MousePos)); // (a finger: a tap puts a point down when it lifts, a drag turns the view)
-                    ImVec2 s0, s1;
+            addDrawPoint(io);
-                    if (drawPts_.size() >= 3 && project(drawPts_[0], s0) && project(*p, s1) && std::hypot(s0.x - s1.x, s0.y - s1.y) < 10) finishShape();
-                    else drawPts_.push_back(*p);
-                }
             return;
         }
         if (tool_ == Tool::Knife) {
@@ -4217,6 +4216,13 @@ private:
             else boxing_ = true, boxStart_ = io.MousePos, touchOrbit_ = touch() && tool_ != Tool::Select; // (a finger: dragging turns the view, but Select's box)
         }
     }
+    void addDrawPoint(const ImGuiIO& io) {
+        if (auto p = drawPoint(io)) {
+            ImVec2 s0, s1;
+            if (drawPts_.size() >= 3 && project(drawPts_[0], s0) && project(*p, s1) && std::hypot(s0.x - s1.x, s0.y - s1.y) < (touch() ? 24 : 10)) finishShape();
+            else drawPts_.push_back(*p);
+        }
+    }
     // Painting: on the model under the mouse.
     void paintViewport(ImGuiIO& io) {
         if (paint_.waiting) {
@@ -4748,7 +4754,7 @@ private:
             }
             if (pts.size() >= 3) dl->AddPolyline(pts.data(), int(pts.size()), hole_.active ? kHot : IM_COL32(255, 255, 255, 200), ImDrawFlags_Closed, 2.0f);
         }
-        if (boxing_ && std::hypot(io.MousePos.x - boxStart_.x, io.MousePos.y - boxStart_.y) > 4) {
+        if (boxing_ && !touchOrbit_ && std::hypot(io.MousePos.x - boxStart_.x, io.MousePos.y - boxStart_.y) > 4) {
             dl->AddRectFilled(boxStart_, io.MousePos, IM_COL32(255, 140, 60, 30));
             dl->AddRect(boxStart_, io.MousePos, kAccent);
         }
@@ -4763,7 +4769,7 @@ private:
                 dl->AddCircleFilled(s, i == 0 ? 6.0f : 4.0f, i == 0 ? IM_COL32(255, 255, 255, 255) : kAccent);
                 prev = s;
             }
-            if (mouseInView(io))
+            if (mouseInView(io) && !touch()) // (a finger isn't hovering anywhere)
                 if (auto p = drawPoint(io); p && project(*p, s)) {
                     if (!drawPts_.empty()) dl->AddLine(prev, s, IM_COL32(255, 160, 90, 180), 1.5f);
                     dl->AddCircle(s, 5.0f, IM_COL32(255, 255, 255, 220), 0, 1.5f);
@@ -4903,9 +4909,19 @@ private:
     void defaultLayout(ImGuiID dock) {
         layoutDone_ = true;
         ImGuiDockNode* node = ImGui::DockBuilderGetNode(dock);
-        if (node && (node->IsSplitNode() || node->Windows.Size)) return; // (the user's own, from the .ini)
+        if (!touch() && node && (node->IsSplitNode() || node->Windows.Size)) return; // (the user's own, from the .ini)
         ImGui::DockBuilderRemoveNodeChildNodes(dock);
+        ImGui::DockBuilderSetNodeSize(dock, ImGui::GetMainViewport()->WorkSize); // (splits are shares of this)
         ImGuiID center = dock;
+        if (touch() && portrait_) { // a phone held upright: the view on top, the panels as tabs under it
+            const ImGuiID bottom = ImGui::DockBuilderSplitNode(center, ImGuiDir_Down, 0.36f, nullptr, &center);
+            const ImVec2 size = ImGui::GetMainViewport()->WorkSize;
+            ImGui::DockBuilderSetNodeSize(bottom, ImVec2(size.x, size.y * 0.36f));
+            for (const char* w : {"Toolbox", "Tool options", "Properties", "Layers", "Picture"}) ImGui::DockBuilderDockWindow(w, bottom);
+            ImGui::DockBuilderFinish(dock);
+            showToolbox_ = true; // (its tab first)
+            return;
+        }
         if (touch()) { // a phone: tools down the left, the panels on the right (shown when asked for)
             ImGuiID left = ImGui::DockBuilderSplitNode(center, ImGuiDir_Left, 0.2f, nullptr, &center);
             const ImGuiID leftBottom = ImGui::DockBuilderSplitNode(left, ImGuiDir_Down, 0.45f, nullptr, &left);
@@ -5134,6 +5150,7 @@ private:
     }
 
     void toolbox() {
+        if (std::exchange(showToolbox_, false)) ImGui::SetNextWindowFocus();
         ImGui::Begin("Toolbox", nullptr, ImGuiWindowFlags_NoCollapse);
         const float w = ImGui::GetContentRegionAvail().x;
         if (tab_ == Tab::Paint) {