[WIP] Viewports backend, 2

imgui-binding/src/main/java/imgui/ImGuiIO.java

@@ -590,6 +590,75 @@ public final class ImGuiIO {
         ImGui::GetIO().ConfigDockingTransparentPayload = value;
     */
 
+    // Viewport options (when ImGuiConfigFlags_ViewportsEnable is set)
+
+    /**
+     * Set to make all floating imgui windows always create their own viewport.
+     * Otherwise, they are merged into the main host viewports when overlapping it. May also set ImGuiViewportFlags_NoAutoMerge on individual viewport.
+     */
+    public native boolean getConfigViewportsNoAutoMerge(); /*
+        return ImGui::GetIO().ConfigViewportsNoAutoMerge;
+    */
+
+    /**
+     * Set to make all floating imgui windows always create their own viewport.
+     * Otherwise, they are merged into the main host viewports when overlapping it. May also set ImGuiViewportFlags_NoAutoMerge on individual viewport.
+     */
+    public native void setConfigViewportsNoAutoMerge(boolean value); /*
+        ImGui::GetIO().ConfigViewportsNoAutoMerge = value;
+    */
+
+    /**
+     * Disable default OS task bar icon flag for secondary viewports. When a viewport doesn't want a task bar icon, ImGuiViewportFlags_NoTaskBarIcon will be set on it.
+     */
+    public native boolean getConfigViewportsNoTaskBarIcon(); /*
+        return ImGui::GetIO().ConfigViewportsNoTaskBarIcon;
+    */
+
+    /**
+     * Disable default OS task bar icon flag for secondary viewports. When a viewport doesn't want a task bar icon, ImGuiViewportFlags_NoTaskBarIcon will be set on it.
+     */
+    public native void setConfigViewportsNoTaskBarIcon(boolean value); /*
+        ImGui::GetIO().ConfigViewportsNoTaskBarIcon = value;
+    */
+
+    /**
+     * [BETA] Disable default OS window decoration flag for secondary viewports. When a viewport doesn't want window decorations,
+     * ImGuiViewportFlags_NoDecoration will be set on it. Enabling decoration can create subsequent issues at OS levels (e.g. minimum window size).
+     */
+    public native boolean getConfigViewportsNoDecoration(); /*
+        return ImGui::GetIO().ConfigViewportsNoDecoration;
+    */
+
+    /**
+     * [BETA] Disable default OS window decoration flag for secondary viewports. When a viewport doesn't want window decorations,
+     * ImGuiViewportFlags_NoDecoration will be set on it. Enabling decoration can create subsequent issues at OS levels (e.g. minimum window size).
+     */
+    public native void setConfigViewportsNoDecoration(boolean value); /*
+        ImGui::GetIO().ConfigViewportsNoDecoration = value;
+    */
+
+    /**
+     * Disable default OS parenting to main viewport for secondary viewports.
+     * By default, viewports are marked with ParentViewportId = <main_viewport>,
+     * expecting the platform back-end to setup a parent/child relationship between the OS windows (some back-end may ignore this).
+     * Set to true if you want the default to be 0, then all viewports will be top-level OS windows.
+     */
+    public native boolean getConfigViewportsNoDefaultParent(); /*
+        return ImGui::GetIO().ConfigViewportsNoDefaultParent;
+    */
+
+    /**
+     * Disable default OS parenting to main viewport for secondary viewports.
+     * By default, viewports are marked with ParentViewportId = <main_viewport>,
+     * expecting the platform back-end to setup a parent/child relationship between the OS windows (some back-end may ignore this).
+     * Set to true if you want the default to be 0, then all viewports will be top-level OS windows.
+     */
+    public native void setConfigViewportsNoDefaultParent(boolean value); /*
+        ImGui::GetIO().ConfigViewportsNoDefaultParent = value;
+    */
+
+
     /**
      * Time elapsed since last frame, in seconds.
      * <p>

imgui-binding/src/main/java/imgui/ImGuiPlatformIO.java

@@ -191,7 +191,7 @@ public final class ImGuiPlatformIO extends ImGuiStruct {
                     JNIEnv* env = Jni::GetEnv();\
                     env->SetLongField(jTmpViewport, Jni::GetBindingStructPtrID(), (intptr_t)vp);\
                     Jni::CallImPlatformFuncViewportSuppImVec2(env, platformCallback##name, jTmpViewport, jTmpImVec2);\
-                    Jni::ImVec2Cpy(env, jTmpImVec2, dst);\
+                    Jni::ImVec2Cpy(env, jTmpImVec2, &dst);\
                 }\
                 return dst;\
             }

imgui-binding/src/main/java/imgui/ImGuiViewport.java

@@ -38,14 +38,14 @@ public final class ImGuiViewport extends ImGuiStruct {
     */
 
     /**
-     * See ImGuiViewportFlags_.
+     * See {@link imgui.flag.ImGuiViewportFlags}.
      */
     public native int getFlags(); /*
         return IMGUI_VIEWPORT->Flags;
     */
 
     /**
-     * See ImGuiViewportFlags_.
+     * See {@link imgui.flag.ImGuiViewportFlags}.
      */
     public native void setFlags(int flags); /*
         IMGUI_VIEWPORT->Flags = flags;

imgui-binding/src/main/java/imgui/glfw/ImGuiImplGlfwNative.java

@@ -0,0 +1,24 @@
+package imgui.glfw;
+
+final class ImGuiImplGlfwNative {
+    private ImGuiImplGlfwNative() {
+    }
+
+    /*JNI
+        #if defined(_WIN32)
+            #include <windows.h>
+        #endif
+     */
+
+    // GLFW hack: Hide icon from task bar
+    // Applied only for windows
+    static native void win32hideFromTaskBar(long hwndPtr); /*
+        #if defined(_WIN32)
+            HWND hwnd = (HWND)hwndPtr;
+            LONG ex_style = ::GetWindowLong(hwnd, GWL_EXSTYLE);
+            ex_style &= ~WS_EX_APPWINDOW;
+            ex_style |= WS_EX_TOOLWINDOW;
+            ::SetWindowLong(hwnd, GWL_EXSTYLE, ex_style);
+        #endif
+    */
+}

imgui-binding/src/main/native/jni_common.cpp

@@ -48,11 +48,6 @@ namespace Jni
         dst->y = env->GetFloatField(src, imVec2YID);
     }
 
-    void ImVec2Cpy(JNIEnv* env, jobject src, ImVec2 dst) {
-        dst.x = env->GetFloatField(src, imVec2XID);
-        dst.y = env->GetFloatField(src, imVec2YID);
-    }
-
     void ImVec4Cpy(JNIEnv* env, ImVec4* src, jobject dst) {
         env->SetFloatField(dst, imVec4XID, src->x);
         env->SetFloatField(dst, imVec4YID, src->y);

imgui-binding/src/main/native/jni_common.h

@@ -14,7 +14,6 @@ namespace Jni
     void ImVec2Cpy(JNIEnv* env, ImVec2 src, jobject dst);
 
     void ImVec2Cpy(JNIEnv* env, jobject src, ImVec2* dst);
-    void ImVec2Cpy(JNIEnv* env, jobject src, ImVec2 dst);
 
     void ImVec4Cpy(JNIEnv* env, ImVec4* src, jobject dst);
     void ImVec4Cpy(JNIEnv* env, ImVec4 src, jobject dst);

imgui-lwjgl3/src/main/java/imgui/glfw/ImGuiImplGlfw.java

@@ -26,6 +26,7 @@ import org.lwjgl.glfw.GLFWErrorCallback;
 import org.lwjgl.glfw.GLFWKeyCallback;
 import org.lwjgl.glfw.GLFWMonitorCallback;
 import org.lwjgl.glfw.GLFWMouseButtonCallback;
+import org.lwjgl.glfw.GLFWNativeWin32;
 import org.lwjgl.glfw.GLFWScrollCallback;
 import org.lwjgl.glfw.GLFWVidMode;
 
@@ -43,6 +44,8 @@ import static org.lwjgl.system.MemoryUtil.NULL;
  * modify the rendering routine in the way you'd like.
  */
 public class ImGuiImplGlfw {
+    protected static final boolean IS_WINDOWS = System.getProperty("os.name", "generic").toLowerCase().contains("win");
+
     // Pointer of the current GLFW window
     private long windowPtr;
 
@@ -239,6 +242,10 @@ public class ImGuiImplGlfw {
         final ImGuiViewport mainViewport = ImGui.getMainViewport();
         mainViewport.setPlatformHandle(windowPtr);
 
+        if (IS_WINDOWS) {
+            mainViewport.setPlatformHandleRaw(GLFWNativeWin32.glfwGetWin32Window(windowId));
+        }
+
         if ((io.getConfigFlags() & ImGuiConfigFlags.ViewportsEnable) != 0) {
             initPlatformInterface();
         }
@@ -528,6 +535,10 @@ public class ImGuiImplGlfw {
 
             vp.setPlatformHandle(data.window);
 
+            if (IS_WINDOWS) {
+                vp.setPlatformHandleRaw(GLFWNativeWin32.glfwGetWin32Window(data.window));
+            }
+
             glfwSetWindowPos(data.window, (int) vp.getPosX(), (int) vp.getPosY());
 
             // Install GLFW callbacks for secondary viewports
@@ -562,6 +573,11 @@ public class ImGuiImplGlfw {
         @Override
         public void accept(final ImGuiViewport vp) {
             final ImGuiViewportDataGlfw data = (ImGuiViewportDataGlfw) vp.getPlatformUserData();
+
+            if (IS_WINDOWS && (vp.getFlags() & ImGuiViewportFlags.NoTaskBarIcon) != 0) {
+                ImGuiImplGlfwNative.win32hideFromTaskBar(vp.getPlatformHandleRaw());
+            }
+
             glfwShowWindow(data.window);
         }
     }
@@ -606,7 +622,7 @@ public class ImGuiImplGlfw {
         public void accept(final ImGuiViewport vp, final ImVec2 imVec2) {
             final ImGuiViewportDataGlfw data = (ImGuiViewportDataGlfw) vp.getPlatformUserData();
             data.ignoreWindowSizeEventFrame = ImGui.getFrameCount();
-            glfwSetWindowSize(data.window, (int) imVec2.y, (int) imVec2.y);
+            glfwSetWindowSize(data.window, (int) imVec2.x, (int) imVec2.y);
         }
     }
 

imgui-lwjgl3/src/test/java/ExampleUi.java

@@ -1,3 +1,4 @@
+import imgui.ImGuiViewport;
 import imgui.type.ImBoolean;
 import imgui.ImColor;
 import imgui.ImGui;
@@ -40,8 +41,10 @@ final class ExampleUi {
     }
 
     void render() {
+        final ImGuiViewport mainViewport = ImGui.getMainViewport();
+
         ImGui.setNextWindowSize(600, 300, ImGuiCond.Once);
-        ImGui.setNextWindowPos(10, 10, ImGuiCond.Once);
+        ImGui.setNextWindowPos(mainViewport.getWorkPosX() + 10, mainViewport.getWorkPosY() + 10, ImGuiCond.Once);
 
         ImGui.begin("Custom window");  // Start Custom window
 

imgui-lwjgl3/src/test/java/ImGuiGlfwExample.java

@@ -12,6 +12,8 @@ import imgui.ImFontConfig;
 import imgui.ImGui;
 import imgui.ImGuiFreeType;
 import imgui.ImGuiIO;
+import imgui.ImGuiStyle;
+import imgui.flag.ImGuiCol;
 import imgui.flag.ImGuiConfigFlags;
 import imgui.gl3.ImGuiImplGl3;
 import imgui.glfw.ImGuiImplGlfw;
@@ -143,7 +145,6 @@ public final class ImGuiGlfwExample {
         // Initialize ImGuiIO config
         final ImGuiIO io = ImGui.getIO();
 
-        io.setMouseDrawCursor(true);
         io.setIniFilename(null); // We don't want to save .ini file
         io.addConfigFlags(ImGuiConfigFlags.NavEnableKeyboard | ImGuiConfigFlags.DockingEnable | ImGuiConfigFlags.ViewportsEnable);
 
@@ -185,6 +186,13 @@ public final class ImGuiGlfwExample {
         // ------------------------------------------------------------
         // Use freetype instead of stb_truetype to build a fonts texture
         ImGuiFreeType.buildFontAtlas(fontAtlas, ImGuiFreeType.RasterizerFlags.LightHinting);
+
+        // When viewports are enabled we tweak WindowRounding/WindowBg so platform windows can look identical to regular ones.
+        if ((io.getConfigFlags() & ImGuiConfigFlags.ViewportsEnable) != 0) {
+            final ImGuiStyle style = ImGui.getStyle();
+            style.setWindowRounding(0.0f);
+            style.setColor(ImGuiCol.WindowBg, ImGui.getColorU32(ImGuiCol.WindowBg, 1));
+        }
     }
 
     // Main application loop