问如何让一个演员呆在舞台里？
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Stack Overflow用户

提问于 2016-01-14 07:57:00

回答 1查看 584关注 0票数 0

我正在用libgdx创建一个游戏，我用舞台和演员来制作游戏中的实体。但问题是我不能让演员呆在舞台或银幕里。当我把演员拖到最低、最高、最左或最右边的屏幕上时，它就会从屏幕上消失。我要它留在屏幕里。

我该怎么办？请帮帮忙。

这是我用来拖动我的演员的代码片段。

addListener(新的DragListener(){ @重写公共布尔型touchDown(InputEvent事件，浮点数x，浮点数y，int指针，int按钮)){ camera.unproject(dimension.set(x，y，0))；System.out.println("clicked "+ x+，“+y”)；返回true；}@覆盖公共空touchDragged(InputEvent事件，浮点数x，浮点数y，int指针){ moveBy(x-(getWidth()/2)，y-(getHeight()/3))；}@覆盖公共super.touchUp(InputEvent事件，浮点数x，浮点数y，int指针，int按钮){super.touchUp(事件，x，y，指针，按钮)；}}；}；

libgdx

scene2d

java

回答 1

Stack Overflow用户

发布于 2016-01-17 16:14:28

Stage确实有getWidth和getHeight方法。它们返回由内部Viewport管理的世界大小。Window类具有可选的拖动行为和keepWithinStage参数。

这是来自LibGDX 1.8.0 (Window类)的代码片段：

        public void touchDragged (InputEvent event, float x, float y, int pointer) {
            if (!dragging) return;
            float width = getWidth(), height = getHeight();
            float windowX = getX(), windowY = getY();

            float minWidth = getMinWidth(), maxWidth = getMaxWidth();
            float minHeight = getMinHeight(), maxHeight = getMaxHeight();
            Stage stage = getStage();
            boolean clampPosition = keepWithinStage && getParent() == stage.getRoot();

            if ((edge & MOVE) != 0) {
                float amountX = x - startX, amountY = y - startY;
                windowX += amountX;
                windowY += amountY;
            }
            if ((edge & Align.left) != 0) {
                float amountX = x - startX;
                if (width - amountX < minWidth) amountX = -(minWidth - width);
                if (clampPosition && windowX + amountX < 0) amountX = -windowX;
                width -= amountX;
                windowX += amountX;
            }
            if ((edge & Align.bottom) != 0) {
                float amountY = y - startY;
                if (height - amountY < minHeight) amountY = -(minHeight - height);
                if (clampPosition && windowY + amountY < 0) amountY = -windowY;
                height -= amountY;
                windowY += amountY;
            }
            if ((edge & Align.right) != 0) {
                float amountX = x - lastX;
                if (width + amountX < minWidth) amountX = minWidth - width;
                if (clampPosition && windowX + width + amountX > stage.getWidth()) amountX = stage.getWidth() - windowX - width;
                width += amountX;
            }
            if ((edge & Align.top) != 0) {
                float amountY = y - lastY;
                if (height + amountY < minHeight) amountY = minHeight - height;
                if (clampPosition && windowY + height + amountY > stage.getHeight())
                    amountY = stage.getHeight() - windowY - height;
                height += amountY;
            }
            lastX = x;
            lastY = y;
            setBounds(Math.round(windowX), Math.round(windowY), Math.round(width), Math.round(height));
        }