Question

如果我要编写一份我想要完成的工作代码，那就是：

Sprite s1(img_path1);
Sprite s2(img_path2);
Sprite s[] = { s1, s2 }

我想在数组声明的{}内创建对象，而不是先将对象放入变量然后放入数组中。

我在询问此问题之前检查了this帖子，我将首先澄清一些事项：

我正在使用-std=c++11
我没有定义自己的复制构造函数

我正在尝试创建一个这样的数组：

Sprite s[] =
{
    Sprite(img_path1),
    Sprite(img_path2)
};

执行该语句后，s的内容与使用默认构造函数创建对象数组的内容相同：

Sprite s[2];

问题似乎与默认的复制构造函数无关，因为以下执行完全正常：

sp = Sprite(img_path);
Sprite sp1(sp);
std::cout << sp1.getAspectRatio();

相关代码：

/*
 * Sprite.h
 *
*/

#ifndef SPRITE_H
#define SPRITE_H

#include <GL/freeglut.h>
#include <FreeImage.h>
#include <iostream>
#include <stdio.h>

class Sprite
{
    GLuint texture;
    float aspectRatio;
    public:
        Sprite();
        Sprite(std::string path);
        Sprite(GLuint texture, float aspectRatio);
        float getAspectRatio();
        void draw(float x, float y, float alpha, float size);
        virtual ~Sprite();
    protected:
    private:
};

#endif // SPRITE_H



/*
 * Sprite.cpp
 *
*/

#include "Sprite.h"

Sprite::Sprite()
{
    //ctor
}

Sprite::Sprite(std::string file) {
    GLuint texture = 0;
    int sWidth, sHeight;
    if (texture == 0)
    {
        FIBITMAP* bitmap = FreeImage_Load(
            FreeImage_GetFileType(file.c_str(), 0),
            file.c_str());

        if (bitmap == NULL) {
            printf("Could no load image file %s\n", file.c_str());
        }

        glGenTextures(1, &texture);
        printf("%d\n", texture);
        glBindTexture(GL_TEXTURE_2D, texture);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

        FIBITMAP *pImage = FreeImage_ConvertTo32Bits(bitmap);
        int nWidth = sWidth = FreeImage_GetWidth(pImage);
        int nHeight = sHeight = FreeImage_GetHeight(pImage);

        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, nWidth, nHeight,
            0, GL_BGRA_EXT, GL_UNSIGNED_BYTE, (void*)FreeImage_GetBits(pImage));

        FreeImage_Unload(pImage);

        FreeImage_Unload(bitmap);
    }
    this->texture = texture;
    this->aspectRatio = (float)sWidth / sHeight;
    if(texture == 0) {
        std::cout << file << std::endl;
    }
}

Sprite::Sprite(GLuint t, float as) : texture(t), aspectRatio(as) {}

void Sprite::draw(float x, float y, float alpha, float size) {
    float h = size;
    float w = size * aspectRatio;
    glPushMatrix();
    glEnable(GL_TEXTURE_2D);
    glBindTexture(GL_TEXTURE_2D, texture);
    glTexEnvf(GL_TEXTURE_2D, GL_TEXTURE_ENV_MODE, GL_MODULATE);
    glDepthMask(GL_FALSE);
    glEnable(GL_BLEND);
    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
    glColor4f(1.0, 1.0, 1.0, alpha);
    glBegin(GL_QUADS);
    glTexCoord2f(0.0f, 0.0f); glVertex2f(x, y);
    glTexCoord2f(0.0f, 1.0f); glVertex2f(x, y + h);
    glTexCoord2f(1.0f, 1.0f); glVertex2f(x + w, y + h);
    glTexCoord2f(1.0f, 0.0f); glVertex2f(x + w, y);
    glEnd();
    glDisable(GL_TEXTURE_2D);
    glDisable(GL_BLEND);
    glDepthMask(GL_TRUE);
    glPopMatrix();
}

float Sprite::getAspectRatio() { return aspectRatio; }

Sprite::~Sprite()
{
    //dtor
}




/*
 * main.cpp (extract)
 *
*/

#include "Globals.h"
#include <GL/freeglut.h>
#include "Sprite.h"

void render();

std::string img_path = "/home/saurabh/Dropbox/Code/C/OpenGL_Game/images/";

Sprite s[] =
{
    Sprite(img_path + "gait-right-1.gif"),
    Sprite(img_path + "gait-right-0.gif"),

    Sprite(img_path + "gait-left-1.gif"),
    Sprite(img_path + "gait-left-0.gif"),

    Sprite(img_path + "gait-top-1.gif"),
    Sprite(img_path + "gait-top-0.gif"),

    Sprite(img_path + "gait-bottom-1.gif"),
    Sprite(img_path + "gait-bottom-0.gif")
};

int main(int argn, char** argc) {
    FreeImage_Initialise();
    glutInit(&argn, argc);
    glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_DEPTH);
    glutInitWindowSize(GV.windowWidth, GV.windowHeight);
    glutCreateWindow("Monogatari");
    glutDisplayFunc(render);
    glutIdleFunc(render);
    glutMainLoop();
    FreeImage_DeInitialise();
}

void render() {
    s[0].draw(0,0,1,0.5);
}

初始化对象数组

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