-4
看起来好像当我试图为freeglut api编写自己的包装时偶然发现了一些奇怪的事情。基本上，我正在编写我自己的小型库，以便更容易地使用freeglut。我正在做的第一件事情之一是试图实现我自己的Color类，它将被馈送到“glClearColor”中。我也拥有它，以便您可以手动输入颜色;这意味着我将拥有多个具有相同名称但参数/参数不同的静态方法。之后我试图编译这个文件，但收到一个错误，让我认为编译器不能决定使用哪种方法 - 考虑到这两种方法仍然不同，这很奇怪。一个采用Color3类，另一个采用Color4。C++具有相同名称但具有不同参数的多个静态函数
下面是一些来源：
GL.H
#pragma once
#include "Vector3.h"
#include "Color3.h"
#include "Color4.h"
#include <string>
class GL
{
public:
static void initializeGL(int argc, char* argv);
static void initializeDisplayMode(unsigned int displayMode);
static void initializeWindowSize(int width, int height);
static void createWindow(std::string title);
static void mainLoop();
static void translate(const Vector3 &location);
static void translate(float x, float y, float z);
static void rotate(double rotation, float x, float y, float z);
static void rotate(double rotation, const Vector3& axis);
static void color3(const Color3 &color);
static void color4(const Color4 &color);
static void begin();
static void end();
static void pushMatrix();
static void popMatrix();
static void enable(int enableCap);
static void viewport();
static void polygonMode();
static void matrixMode();
static void clearColor(const Color3 &color);
static void clearColor(float red, float green, float blue);
static void clearColor(float red, float green, float blue, float alpha);
static void clearColor(const Color4 &color);
static void vertex3(const Vector3 &location);
static void vertex3(float x, float y, float z);
static void loadIdentity();
static void perspective();
static void depthFunction();
};
GL.cpp
#include "GL.h"
#include "freeglut.h"
void GL::clearColor(const Color3 &color)
{
glClearColor(color.getRed,color.getGreen,color.getBlue, 1.0f);
}
void GL::clearColor(float red, float green, float blue)
{
glClearColor(red, green, blue, 1.0f);
}
void GL::clearColor(float red, float green, float blue, float alpha)
{
}
void GL::clearColor(const Color4 &color)
{
}
这里是我的编译器错误：
1>------ Build started: Project: GameEngineToolkit, Configuration: Debug Win32 ------
1> Main.cpp
1>c:\the capsule\c++\get\gameenginetoolkit\gameenginetoolkit\main.cpp(47): error C2665: 'GL::clearColor' : none of the 4 overloads could convert all the argument types
1> c:\the capsule\c++\get\gameenginetoolkit\gameenginetoolkit\gl.h(610): could be 'void GL::clearColor(const Color4 &)'
1> c:\the capsule\c++\get\gameenginetoolkit\gameenginetoolkit\gl.h(607): or 'void GL::clearColor(const Color3 &)'
1> while trying to match the argument list '(Color3 *)'
1> GL.cpp
1>c:\the capsule\c++\get\gameenginetoolkit\gameenginetoolkit\gl.cpp(8): error C3867: 'Color3::getRed': function call missing argument list; use '&Color3::getRed' to create a pointer to member
1>c:\the capsule\c++\get\gameenginetoolkit\gameenginetoolkit\gl.cpp(8): error C3867: 'Color3::getGreen': function call missing argument list; use '&Color3::getGreen' to create a pointer to member
1>c:\the capsule\c++\get\gameenginetoolkit\gameenginetoolkit\gl.cpp(8): error C3867: 'Color3::getBlue': function call missing argument list; use '&Color3::getBlue' to create a pointer to member
1> Generating Code...
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========
，你可以看，这似乎是编译呃不能决定使用Color3函数还是使用color4函数;我不明白为什么，因为它明显应该选择哪一个（Color3是我主要使用的那个）。
根据要求，这里是我的COLOR3类：
Color3.h
#pragma once
class Color3
{
public:
Color3();
Color3(float red, float green, float blue);
void setRed(float red);
void setGreen(float green);
void setBlue(float blue);
float getRed();
float getGreen();
float getBlue();
Color3 getColor();
~Color3();
private:
float red;
float green;
float blue;
};
Color3.cpp
#include "Color3.h"
Color3::Color3()
{
}
Color3::Color3(float red, float green, float blue)
{
setRed(red);
setGreen(green);
setBlue(blue);
}
Color3::~Color3()
{
}
float Color3::getRed()
{
return red;
}
float Color3::getGreen()
{
return green;
}
float Color3::getBlue()
{
return blue;
}
void Color3::setBlue(float blue)
{
this->blue = blue;
}
void Color3::setGreen(float green)
{
this->green = green;
}
void Color3::setRed(float red)
{
this->red = red;
}
Color3 Color3::getColor()
{
return *this;
}
解决方案：
使用指针。
GL.cpp
#include "GL.h"
#include "freeglut.h"
void GL::clearColor(Color3* color)
{
glClearColor(color->getRed(),color->getGreen(),color->getBlue(), 1.0f);
}
void GL::clearColor(float red, float green, float blue)
{
glClearColor(red, green, blue, 1.0f);
}
void GL::clearColor(float red, float green, float blue, float alpha)
{
}
void GL::clearColor(Color4* color)
{
}
GL.H
#pragma once
#include "Vector3.h"
#include "Color3.h"
#include "Color4.h"
#include <string>
class GL
{
public:
static void initializeGL(int argc, char* argv);
static void initializeDisplayMode(unsigned int displayMode);
static void initializeWindowSize(int width, int height);
static void createWindow(std::string title);
static void mainLoop();
static void translate(const Vector3 &location);
static void translate(float x, float y, float z);
static void rotate(double rotation, float x, float y, float z);
static void rotate(double rotation, const Vector3& axis);
static void color3(const Color3 &color);
static void color4(const Color4 &color);
static void begin();
static void end();
static void pushMatrix();
static void popMatrix();
static void enable(int enableCap);
static void viewport();
static void polygonMode();
static void matrixMode();
static void clearColor(Color3* color); // Use pointers instead
static void clearColor(float red, float green, float blue);
static void clearColor(float red, float green, float blue, float alpha);
static void clearColor(Color4* color); // Same thing; no error. =P
static void vertex3(const Vector3 &location);
static void vertex3(float x, float y, float z);
static void loadIdentity();
static void perspective();
static void depthFunction();
};
它应该是'color.getRed（）'而不是'color.getRed'吗？ – 2014-09-02 18:59:40
第一个错误消息毫不含糊地告诉你'Color3 *'和'const Color3'是两个不同的东西。 – 2014-09-02 19:06:55
http://postimg.org/image/jgclkszxh/ – Krythic 2014-09-02 19:07:09