widget.cpp:170:33: error: no viable conversion from 'osgEarth::SkyNode *' to 'osg::ref_ptr<osg::Drawable>' ref_ptr:37:9: note: candidate constructor not viable: no known conversion from 'osgEarth::SkyNode *' to 'osg::Drawable *' for 1st argument ref_ptr:38:9: note: candidate constructor not viable: no known conversion from 'osgEarth::SkyNode *' to 'const osg::ref_ptr<osg::Drawable> &' for 1st argument ref_ptr:40:9: note: candidate constructor not viable: no known conversion from 'osgEarth::SkyNode *' to 'observer_ptr<osg::Drawable> &' for 1st argument ref_ptr:39:31: note: candidate template ignored: could not match 'ref_ptr<type-parameter-0-0>' against 'osgEarth::SkyNode *'
时间: 2024-02-06 14:01:58 浏览: 157
看起来你正在将 `osgEarth::SkyNode` 类型的对象直接赋值给了 `osg::ref_ptr<osg::Drawable>` 类型的变量,这是不兼容的,因为 `SkyNode` 并不是继承自 `Drawable`。
正确的写法应该是创建一个 `osg::Geode` 对象,将 `SkyNode` 添加到 `osg::Geode` 中,然后将 `osg::Geode` 添加到场景图中。以下是一个示例代码:
```
osg::ref_ptr<osg::Geode> skyGeode = new osg::Geode();
osg::ref_ptr<osgEarth::Util::SkyNode> skyNode = new osgEarth::Util::SkyNode(osgEarth::Util::SkyOptions());
skyGeode->addDrawable(skyNode.get());
root->addChild(skyGeode.get());
```
这将创建一个 `osgEarth::Util::SkyNode` 对象,并将其添加到 `osg::Geode` 中,然后将 `osg::Geode` 添加到场景图中。
相关问题
你给的代码报错form_para.cpp:340:14: No matching function for call to 'swap' move.h:182:5: candidate function [with _Tp = QByteRef] not viable: expects an lvalue for 1st argument stl_bvector.h:114:3: candidate function not viable: no known conversion from 'QByteRef' to 'std::_Bit_reference' for 1st argument stl_bvector.h:122:3: candidate function not viable: no known conversion from 'QByteRef' to 'std::_Bit_reference' for 1st argument stl_bvector.h:130:3: candidate function not viable: no known conversion from 'QByteRef' to 'bool &' for 1st argument move.h:205:5: candidate template ignored: could not match '_Tp[_Nm]' against 'QByteRef' stl_pair.h:490:5: candidate template ignored: could not match 'pair<_T1, _T2>' against 'QByteRef' stl_pair.h:498:5: candidate template ignored: could not match 'pair<_T1, _T2>' against 'QByteRef' ... shared_ptr_base.h:1738:5: candidate template ignored: could not match '__weak_ptr<_Tp, _Lp>' against 'QByteRef' shared_ptr.h:490:5: candidate template ignored: could not match 'shared_ptr<_Tp>' against 'QByteRef' shared_ptr.h:611:5: candidate template ignored: could not match 'weak_ptr<_Tp>' against 'QByteRef'
非常抱歉,我的代码还是有误。QByteArray的swap函数确实只接受一个参数。如果要交换两个字节的高低位,可以使用以下代码:
```cpp
uint16_t value = 0x1234; // 待转换的uint16_t值
QByteArray bytes(reinterpret_cast<const char*>(&value), sizeof(value)); // 将uint16_t转换成QByteArray
char temp = bytes[0];
bytes[0] = bytes[1];
bytes[1] = temp;
QString str(bytes); // 将QByteArray转换成QString
```
在上述代码中,我们使用一个临时变量temp来交换QByteArray中的两个字节的高低位。最终,输出的字符串为:"4321"。
请注意,上述代码假定机器采用的是little-endian格式,即低地址存放的是值的低位字节。如果机器采用的是big-endian格式,即低地址存放的是值的高位字节,则需要交换QByteArray中的第0个字节和第1个字节。
widget.cpp:29:18: error: no matching conversion for static_cast from 'char [1024]' to 'Widget::Result' widget.h:46:13: note: candidate constructor (the implicit copy constructor) not viable: no known conversion from 'char [1024]' to 'const Widget::Result' for 1st argument widget.h:46:13: note: candidate constructor (the implicit move constructor) not viable: no known conversion from 'char [1024]' to 'Widget::Result' for 1st argument widget.h:46:13: note: candidate constructor (the implicit default constructor) not viable: requires 0 arguments, but 1 was provided
这个错误发生的原因是你试图将一个 char 数组转换为 Widget::Result 类型的对象,但是 Widget::Result 类型没有定义接受 char 数组作为参数的构造函数或转换函数,因此编译器无法完成这个转换。
为了解决这个问题,你需要修改 Widget 类的构造函数,使其可以接受一个 char* 类型的指针,并将其转换为 Widget::Result 类型的对象。以下是一个示例代码:
```c++
#include <iostream>
#include <cstring>
using namespace std;
class Widget {
public:
struct Result { int x; int y; };
Widget(char* data) {
memcpy(&result_, data, sizeof(Result));
}
Result* GetResult() {
return &result_;
}
private:
Result result_;
};
int main() {
char data[] = { 0x01, 0x00, 0x00, 0x00, 0x02, 0x00, 0x00, 0x00 };
Widget widget(static_cast<char*>(data));
Widget::Result* result = widget.GetResult();
cout << "x: " << result->x << ", y: " << result->y << endl;
return 0;
}
```
在这个示例中,我们修改了 Widget 类的构造函数,使用 memcpy 函数将 char* 类型的指针转换为 Widget::Result 类型的对象。然后我们使用 static_cast 将 char 数组转换为 char* 类型的指针,并将其传递给 Widget 类的构造函数。这样就可以安全地访问 result_ 成员变量了。
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