Revert "plugins/zoom: Port to CursorItem"

This reverts commit e40f632c9b.

It broke non default mouse tracking modes. There are just too many
options, so revert the change instead.

src/plugins/zoom/zoom.cpp

@@ -26,11 +26,8 @@
 
 #include "core/rendertarget.h"
 #include "core/renderviewport.h"
-#include "cursor.h"
 #include "effect/effecthandler.h"
 #include "opengl/glutils.h"
-#include "scene/cursoritem.h"
-#include "scene/workspacescene.h"
 
 using namespace std::chrono_literals;
 
@@ -46,6 +43,7 @@ ZoomEffect::ZoomEffect()
     , mouseTracking(MouseTrackingProportional)
     , mousePointer(MousePointerScale)
     , focusDelay(350) // in milliseconds
+    , isMouseHidden(false)
     , xMove(0)
     , yMove(0)
     , moveFactor(20.0)
@@ -161,12 +159,36 @@ bool ZoomEffect::isTextCaretTrackingEnabled() const
 #endif
 }
 
+GLTexture *ZoomEffect::ensureCursorTexture()
+{
+    if (!m_cursorTexture || m_cursorTextureDirty) {
+        m_cursorTexture.reset();
+        m_cursorTextureDirty = false;
+        const auto cursor = effects->cursorImage();
+        if (!cursor.image().isNull()) {
+            m_cursorTexture = GLTexture::upload(cursor.image());
+            if (!m_cursorTexture) {
+                return nullptr;
+            }
+            m_cursorTexture->setWrapMode(GL_CLAMP_TO_EDGE);
+        }
+    }
+    return m_cursorTexture.get();
+}
+
+void ZoomEffect::markCursorTextureDirty()
+{
+    m_cursorTextureDirty = true;
+}
+
 void ZoomEffect::showCursor()
 {
-    if (m_cursorHidden) {
-        m_cursorItem.reset();
-        m_cursorHidden = false;
+    if (isMouseHidden) {
+        disconnect(effects, &EffectsHandler::cursorShapeChanged, this, &ZoomEffect::markCursorTextureDirty);
+        // show the previously hidden mouse-pointer again and free the loaded texture/picture.
         effects->showCursor();
+        m_cursorTexture.reset();
+        isMouseHidden = false;
     }
 }
 
@@ -175,17 +197,16 @@ void ZoomEffect::hideCursor()
     if (mouseTracking == MouseTrackingProportional && mousePointer == MousePointerKeep) {
         return; // don't replace the actual cursor by a static image for no reason.
     }
-    if (!m_cursorHidden) {
-        effects->hideCursor();
-        m_cursorHidden = true;
-
-        if (mousePointer == MousePointerKeep || mousePointer == MousePointerScale) {
-            Cursor *cursor = Cursors::self()->mouse();
-            m_cursorItem = std::make_unique<CursorItem>(effects->scene()->overlayItem());
-            m_cursorItem->setPosition(cursor->pos());
-            connect(cursor, &Cursor::posChanged, m_cursorItem.get(), [this, cursor]() {
-                m_cursorItem->setPosition(cursor->pos());
-            });
+    if (!isMouseHidden) {
+        // try to load the cursor-theme into a OpenGL texture and if successful then hide the mouse-pointer
+        GLTexture *texture = nullptr;
+        if (effects->isOpenGLCompositing()) {
+            texture = ensureCursorTexture();
+        }
+        if (texture) {
+            effects->hideCursor();
+            connect(effects, &EffectsHandler::cursorShapeChanged, this, &ZoomEffect::markCursorTextureDirty);
+            isMouseHidden = true;
         }
     }
 }
@@ -245,9 +266,6 @@ void ZoomEffect::prePaintScreen(ScreenPrePaintData &data, std::chrono::milliseco
         showCursor();
     } else {
         hideCursor();
-        if (mousePointer == MousePointerScale) {
-            m_cursorItem->setTransform(QTransform::fromScale(zoom, zoom));
-        }
     }
 
     effects->prePaintScreen(data, presentTime);
@@ -386,6 +404,34 @@ void ZoomEffect::paintScreen(const RenderTarget &renderTarget, const RenderViewp
         offscreen.texture->render(offscreen.viewport.size() * scale);
     }
     ShaderManager::instance()->popShader();
+
+    if (mousePointer != MousePointerHide) {
+        // Draw the mouse-texture at the position matching to zoomed-in image of the desktop. Hiding the
+        // previous mouse-cursor and drawing our own fake mouse-cursor is needed to be able to scale the
+        // mouse-cursor up and to re-position those mouse-cursor to match to the chosen zoom-level.
+
+        GLTexture *cursorTexture = ensureCursorTexture();
+        if (cursorTexture) {
+            const auto cursor = effects->cursorImage();
+            QSizeF cursorSize = QSizeF(cursor.image().size()) / cursor.image().devicePixelRatio();
+            if (mousePointer == MousePointerScale) {
+                cursorSize *= zoom;
+            }
+
+            const QPointF p = (effects->cursorPos() - cursor.hotSpot()) * zoom + QPoint(xTranslation, yTranslation);
+
+            glEnable(GL_BLEND);
+            glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+            auto s = ShaderManager::instance()->pushShader(ShaderTrait::MapTexture | ShaderTrait::TransformColorspace);
+            s->setColorspaceUniformsFromSRGB(renderTarget.colorDescription());
+            QMatrix4x4 mvp = viewport.projectionMatrix();
+            mvp.translate(p.x() * scale, p.y() * scale);
+            s->setUniform(GLShader::Mat4Uniform::ModelViewProjectionMatrix, mvp);
+            cursorTexture->render(cursorSize * scale);
+            ShaderManager::instance()->popShader();
+            glDisable(GL_BLEND);
+        }
+    }
 }
 
 void ZoomEffect::postPaintScreen()

src/plugins/zoom/zoom.h

@@ -23,7 +23,6 @@ namespace KWin
 class ZoomAccessibilityIntegration;
 #endif
 
-class CursorItem;
 class GLFramebuffer;
 class GLTexture;
 class GLVertexBuffer;
@@ -97,7 +96,9 @@ private:
         QRect viewport;
     };
 
+    GLTexture *ensureCursorTexture();
     OffscreenData *ensureOffscreenData(const RenderTarget &renderTarget, const RenderViewport &viewport, Output *screen);
+    void markCursorTextureDirty();
 
 #if HAVE_ACCESSIBILITY
     ZoomAccessibilityIntegration *m_accessibilityIntegration = nullptr;
@@ -126,8 +127,9 @@ private:
     QPoint prevPoint;
     QTime lastMouseEvent;
     QTime lastFocusEvent;
-    std::unique_ptr<CursorItem> m_cursorItem;
-    bool m_cursorHidden = false;
+    std::unique_ptr<GLTexture> m_cursorTexture;
+    bool m_cursorTextureDirty = false;
+    bool isMouseHidden;
     QTimeLine timeline;
     int xMove, yMove;
     double moveFactor;