kwin: Split WindowQuadDecoration into two types

Split WindowQuadDecoration into WindowQuadDecorationLeftRight
and WindowQuadDecorationTopBottom.

This simplifies the code in SceneOpenGL::Window::paintDecoration().

libkwineffects/kwineffects.h

@@ -179,7 +179,8 @@ X-KDE-Library=kwin4_effect_cooleffect
 enum WindowQuadType {
     WindowQuadError, // for the stupid default ctor
     WindowQuadContents,
-    WindowQuadDecoration,
+    WindowQuadDecorationLeftRight,
+    WindowQuadDecorationTopBottom,
     // Shadow Quad types
     WindowQuadShadowTop,
     WindowQuadShadowTopRight,
@@ -2679,7 +2680,8 @@ inline
 bool WindowQuad::decoration() const
 {
     assert(quadType != WindowQuadError);
-    return quadType == WindowQuadDecoration;
+    return quadType == WindowQuadDecorationLeftRight ||
+           quadType == WindowQuadDecorationTopBottom;
 }
 
 inline

scene.cpp

@@ -748,6 +748,13 @@ WindowQuadList Scene::Window::makeDecorationQuads(const QRect *rects, const QReg
         QPoint(-rects[3].x(),                    -rects[3].y() + rects[1].height())  // Bottom
     };
 
+    const WindowQuadType types[4] = {
+        WindowQuadDecorationLeftRight, // Left
+        WindowQuadDecorationTopBottom, // Top
+        WindowQuadDecorationLeftRight, // Right
+        WindowQuadDecorationTopBottom  // Bottom
+    };
+
     for (int i = 0; i < 4; i++) {
         foreach (const QRect &r, (region & rects[i]).rects()) {
             if (!r.isValid())
@@ -763,7 +770,7 @@ WindowQuadList Scene::Window::makeDecorationQuads(const QRect *rects, const QReg
             const int u1 = x1 + offsets[i].x();
             const int v1 = y1 + offsets[i].y();
 
-            WindowQuad quad(WindowQuadDecoration);
+            WindowQuad quad(types[i]);
             quad[0] = WindowVertex(x0, y0, u0, v0); // Top-left
             quad[1] = WindowVertex(x1, y0, u1, v0); // Top-right
             quad[2] = WindowVertex(x1, y1, u1, v1); // Bottom-right

scene_opengl.cpp

@@ -1156,24 +1156,26 @@ void SceneOpenGL::Window::paintDecorations(const WindowPaintData &data, const QR
     }
 
     WindowQuadList quads[2]; // left-right, top-bottom
-    GLTexture *textures[2];
-
-    QRect rect[4];
-    t->layoutDecorationRects(rect[0], rect[1], rect[2], rect[3], Client::WindowRelative);
 
     // Split the quads into two lists
     foreach (const WindowQuad &quad, data.quads) {
-        if (quad.type() != WindowQuadDecoration)
+        switch (quad.type()) {
+        case WindowQuadDecorationLeftRight:
+            quads[0].append(quad);
             continue;
 
-        for (int i = 0; i < 4; i++) {
-            if (rect[i].contains(QPoint(quad.originalLeft(), quad.originalTop())))
-                quads[i % 2].append(quad);
+        case WindowQuadDecorationTopBottom:
+            quads[1].append(quad);
+            continue;
+
+        default:
+            continue;
         }
     }
 
     redirector->ensurePixmapsPainted();
 
+    GLTexture *textures[2];
     textures[0] = redirector->leftRightTexture();
     textures[1] = redirector->topBottomTexture();