Getting dpi scale by Display in Linux.

skiko/src/jvmMain/cpp/linux/drawlayer.cc

@@ -255,23 +255,43 @@ extern "C"
         return 1;
     }
 
-    double getDpiScale()
+    JNIEXPORT jfloat JNICALL Java_org_jetbrains_skiko_PlatformOperationsKt_linuxGetDpiScaleNative(JNIEnv *env, jobject properties, jobject component)
     {
-        Display *display = XOpenDisplay(nullptr);
-        if (display != nullptr)
+        JAWT awt;
+        JAWT_DrawingSurface *ds = NULL;
+        JAWT_DrawingSurfaceInfo *dsi = NULL;
+
+        jboolean result = JNI_FALSE;
+        jint lock = 0;
+        JAWT_X11DrawingSurfaceInfo *dsi_x11;
+
+        awt.version = (jint)JAWT_VERSION_9;
+        result = Skiko_GetAWT(env, &awt);
+
+        if (result == JNI_FALSE)
         {
-            double result = getDpiScaleByDisplay(display);
-            XCloseDisplay(display);
-            return result;
+            fprintf(stderr, "JAWT_GetAWT failed! Result is JNI_FALSE\n");
+            return -1;
         }
-        else
+
+        if (jvm == NULL)
         {
-            return 1;
+            env->GetJavaVM(&jvm);
         }
-    }
 
-    JNIEXPORT jfloat JNICALL Java_org_jetbrains_skiko_PlatformOperationsKt_linuxGetDpiScaleNative(JNIEnv *env, jobject properties)
-    {
-        return (float)getDpiScale();
+        ds = awt.GetDrawingSurface(env, component);
+        lock = ds->Lock(ds);
+        dsi = ds->GetDrawingSurfaceInfo(ds);
+        dsi_x11 = (JAWT_X11DrawingSurfaceInfo *)dsi->platformInfo;
+
+        Display *display = dsi_x11->display;
+
+        float dpi = (float)getDpiScaleByDisplay(display);
+
+        ds->FreeDrawingSurfaceInfo(dsi);
+        ds->Unlock(ds);
+        awt.FreeDrawingSurface(ds);
+
+        return dpi;
     }
 } // extern "C"
\ No newline at end of file

skiko/src/jvmMain/kotlin/org/jetbrains/skiko/PlatformOperations.kt

@@ -59,7 +59,7 @@ internal val platformOperations: PlatformOperations by lazy {
                 }
 
                 override fun getDpiScale(component: Component): Float {
-                    return linuxGetDpiScaleNative()
+                    return linuxGetDpiScaleNative(component)
                 }
             }
         }
@@ -71,4 +71,4 @@ external private fun osxIsFullscreenNative(component: Component): Boolean
 external private fun osxSetFullscreenNative(component: Component, value: Boolean)
 
 // Linux
-external private fun linuxGetDpiScaleNative(): Float
+external private fun linuxGetDpiScaleNative(component: Component): Float

skiko/src/jvmMain/kotlin/org/jetbrains/skiko/SkiaLayer.kt

@@ -13,13 +13,7 @@ import org.jetbrains.skija.SurfaceOrigin
 import org.jetbrains.skija.ClipMode
 
 private class SkijaState {
-    val canvasBleach: () -> Unit
-    init {
-        when (hostOs) {
-            OS.MacOS -> canvasBleach = { canvas?.clear(0) }
-            else -> canvasBleach = { canvas?.clear(-1) }
-        }
-    }
+    val bleachConstant = if (hostOs == OS.MacOS) 0 else -1
     var context: DirectContext? = null
     var renderTarget: BackendRenderTarget? = null
     var surface: Surface? = null
@@ -71,7 +65,7 @@ open class SkiaLayer() : HardwareLayer() {
         }
         initSkija()
         skijaState.apply {
-            canvasBleach.invoke()
+            canvas!!.clear(bleachConstant)
             
             // cliping
             for (component in clipComponets) {