c++ - 使用 GLM 的最佳 glMatrixMode() 是什么？

Question

我的下一个问题（或问题）是，当我用 glm 加载模型时，我能够看穿模型的某些部分，例如：如果有两座山在另一座前面，我可以看穿更近的山.

我会展示一张图片，但由于纹理不起作用，因此无法理解。

这里的问题是：

旧的东西：vvvvvvvvvvvvvvvvvvvvvvv

我想知道的是：使用 glm 的最佳矩阵模式是什么？

我已经习惯了 GL_PROJECTION 但是在加载我的模型时它给了我太多的问题

并且使用 GL_MODELVIEW 我无法将相机移回

我也想知道：如果我使用 GL_MODELVIEW，那么如何在场景中移动“相机”？有没有办法设置一个，因为我最终必须这样做？

编辑：好的，这里有一些代码可以给你们一些愿景：

#include <SFML/Graphics.hpp>
#include <SFML/Window.hpp>
#include <iostream>
#include <string>
#include <stdio.h>
#include <fstream>
#include <assert.h>
#include <vector>
#include <glm/glm.h>
#include <glm/glmint.h>
#include "Item.hpp"
#include "Player.hpp"

///GOLD WAVE
using namespace std;
///GLOBAL VARIABLES
vector<sf::Sprite> SpriteList;
vector<GLMmodel*> ModelList;
vector<GLuint> _texture;
vector<Item*> DefItemList;
Player *pPlayer=new Player();

sf::RenderWindow GameWind(sf::VideoMode(800,600,32),"Carperon Game Window",sf::Style::Titlebar);
sf::View GameView(sf::FloatRect(0,0,25,18.75));//65x45 and 8x  0,0,65,45

///PROTOTYPE FUNCTIONS
void SFMLcreate();
void SFMLdraw();
void GLMcreate();
void GLdraw();
GLuint LoadTexture();
void GLiniti();
void ITEMdefault();
///////////////////////////////////STOP PROTOTYPES//////////////////////////////
//////////////////////////////////FUNCTIONS//////////////////////////////////
int main()
{
    GLiniti();
    SFMLcreate();
    GLMcreate();
    ITEMdefault();
    sf::Event EventMain;
    vector<sf::Sprite> ShowingBag;
    sf::Image isbItem[45],iseItem[6];
    sf::Sprite sbItem[45],seItem[6];
    int BagSlotX[45] {0,15,30,0,15,30,0,15,30,0,15,30,0,15,30,0,15,30,0,15,30,0,15,30,0,15,30,0,15,30,0,15,30,0,15,30,0,15,30,0,15,30,0,15,30};
    int BagSlotY[45] {0,0,0,15,15,15,30,30,30,0,0,0,15,15,15,30,30,30,0,0,0,15,15,15,30,30,30,0,0,0,15,15,15,30,30,30,0,0,0,15,15,15,30,30,30};
    int EquipSlotY[6] {0,15,30,0,15,30};
    bool BagUpdate = true;
    int click = 0;
    ///MAIN PLAYER
    pPlayer->PlayerCreate("Molma");
    pPlayer->EquipFill(DefItemList[0]);

    pPlayer->AddItem(DefItemList[1]);
    pPlayer->AddItem(DefItemList[2]);
    pPlayer->AddItem(DefItemList[3]);
    pPlayer->AddItem(DefItemList[4]);

    while(GameWind.IsOpened())
    {
        while(GameWind.GetEvent(EventMain))
        {
            //If its closed
            if(EventMain.Type==sf::Event::Closed)
            {
                //Close the whole thing!
                //GameWind.Close();
                GameWind.Close();
            }
        }
        float MouseX = (GameWind.GetInput().GetMouseX()/32.f);
        float MouseY = (GameWind.GetInput().GetMouseY()/32.f);
        if(GameWind.GetInput().IsKeyDown(sf::Key::Escape))
        {
            GameWind.Close();
            //GameWind.Close();
        }
/////////////////////////////BEGIN INPUT/////////////////////////////////////////////////
        if(GameWind.GetInput().IsKeyDown(sf::Key::Return))
        {
            pPlayer->RandHealth();
            BagUpdate = true;

        }
        if(GameWind.GetInput().IsKeyDown(sf::Key::Z))
        {
            pPlayer->GetHit();
        }

        if(GameWind.GetInput().IsMouseButtonDown(sf::Mouse::Right)&&click<=0)
        {
            for(int a=0;a<pPlayer->Bag.size();++a)
            {
                if(MouseX>((17.f+(BagSlotX[a]))/16.f)&&MouseX<(((32.f+(BagSlotX[a]))/16.f))&&MouseY>((60.f+(BagSlotY[a]))/16.f)&&MouseY<(((75.f+(BagSlotY[a]))/16.f)))
                {
                    pPlayer->ItemUse(pPlayer->Bag[a],a);
                    BagUpdate = true;
                    click=20;
                        //cout << "Item used!" << endl;
                }
            }
            for(int b=0;b<6;++b)
            {
                if(MouseX>2.f/16.f&&MouseX<17.f/16.f&&MouseY>((60.f+(EquipSlotY[b]))/16.f)&&MouseY<((75.f+(EquipSlotY[b]))/16.f)&&pPlayer->EqSpot[b]->get_Type()!="Blank Spot")
                {
                    pPlayer->Unequip(pPlayer->EqSpot[b],DefItemList[0],b);
                    BagUpdate = true;
                    click=20;
                }
            }
        }
///////////////////////////////END INPUT/////////////////////////////////////////////////

//////////////////////////////AUTO FUNCTIONS//////////////////////////////////////////////

        pPlayer->Guarding();
        pPlayer->HitTiming();
        if(BagUpdate)
        {
            for(int a=0;a<pPlayer->Bag.size();++a)
            {
                isbItem[a].LoadFromFile("Graphics/Items.png");
                sbItem[a].SetImage(isbItem[a]);
                sbItem[a].SetPosition(((17.f+(BagSlotX[a]))/16.f),((60.f+(BagSlotY[a]))/16.f));
            }
            for(int b=0;b<6;++b)
            {
                    iseItem[b].LoadFromFile("Graphics/Items.png");
                    seItem[b].SetImage(iseItem[b]);
                    seItem[b].SetPosition(2.f/16.f,((60.f+(EquipSlotY[b]))/16.f));
            }
            BagUpdate=false;
        }
        if(click>0)
        {
            click-=1;
        }

        SpriteList[22].SetPosition(MouseX,MouseY);

        GameWind.SetView(GameView);
        GLdraw();
        SFMLdraw();

        for(int a=((pPlayer->get_BagShow())*9);a<((pPlayer->get_BagShow()*9)+9);++a)//18-27=A
        {
            if(a<pPlayer->Bag.size())
            {

            sbItem[a].Resize(15.f/16.f,15.f/16.f);
            sbItem[a].SetSubRect(sf::IntRect((pPlayer->Bag[a]->get_Index()*15),0,((pPlayer->Bag[a]->get_Index()*15)+15),15));
            GameWind.Draw(sbItem[a]);
            //cout << "Items Drawn! Position: " << BagSlotX[a] << "," << BagSlotY[a] << "Item: " << a << endl;
                //image pos resize subrect
            }
        }
        for(int b=((pPlayer->get_EquipShow())*3);b<((pPlayer->get_EquipShow()*3)+3);++b)
        {

                seItem[b].Resize(15.f/16.f,15.f/16.f);
                seItem[b].SetSubRect(sf::IntRect((pPlayer->EqSpot[b]->get_Index()*15),0,((pPlayer->EqSpot[b]->get_Index()*15)+15),15));
                GameWind.Draw(seItem[b]);

        }

        GameWind.Draw(SpriteList[16]);
        GameWind.Draw(SpriteList[20]);
        GameWind.Draw(SpriteList[21]);
        GameWind.Draw(SpriteList[22]);
        GameWind.Display();
        GameWind.SetFramerateLimit(60);
    }
    return EXIT_SUCCESS;
}



void SFMLcreate()
{
    sf::Image iStatBack,iStatWindow,ipHealth,ipEnergy,ipStr,ipDex,ipInt,ipEnd,ipCrit,ipSwd,ipAxe,ipBow,ipStar,ipWand,ipStaff,ipBag,ipEquip,ipSkills,ipNumHP,ipNumEP,ipGuard,ipRank,ipRankXP,iCursor;
    sf::Sprite StatBack,StatWindow,pHealth,pEnergy,pStr,pDex,pInt,pEnd,pCrit,pSwd,pAxe,pBow,pStar,pWand,pStaff,pBag,pEquip,pSkills,pNumHP,pNumEP,pGuard,pRank,pRankXP,Cursor;
    sf::Font MainFont;

    //LoadFromFile
    iStatBack.LoadFromFile("Graphics/Player Stats/Stats Back.png");
    iStatWindow.LoadFromFile("Graphics/Player Stats/StatWindow2.png");
    ipHealth.LoadFromFile("Graphics/Player Stats/Health.png");
    ipEnergy.LoadFromFile("Graphics/Player Stats/Energy.png");
    ipStr.LoadFromFile("Graphics/Player Stats/Strength.png");
    ipDex.LoadFromFile("Graphics/Player Stats/Dexterity.png");
    ipInt.LoadFromFile("Graphics/Player Stats/Intellegence.png");
    ipEnd.LoadFromFile("Graphics/Player Stats/Endurance.png");
    ipCrit.LoadFromFile("Graphics/Player Stats/Critical.png");
    ipSwd.LoadFromFile("Graphics/Player Stats/Sword Mast.png");
    ipAxe.LoadFromFile("Graphics/Player Stats/Axe Mast.png");
    ipBow.LoadFromFile("Graphics/Player Stats/Bow Mast.png");
    ipStar.LoadFromFile("Graphics/Player Stats/Star Mast.png");
    ipWand.LoadFromFile("Graphics/Player Stats/Wand Mast.png");
    ipStaff.LoadFromFile("Graphics/Player Stats/Staff Mast.png");
    ipBag.LoadFromFile("Graphics/Player Stats/Bag.png");
    ipEquip.LoadFromFile("Graphics/Player Stats/Bag.png");
    ipSkills.LoadFromFile("Graphics/Player Stats/Skill.png");
    ipNumHP.LoadFromFile("Graphics/Player Stats/Number HE.png");
    ipNumEP.LoadFromFile("Graphics/Player Stats/Number HE.png");
    ipGuard.LoadFromFile("Graphics/Player Stats/Guard.png");
    ipRank.LoadFromFile("Graphics/Player Stats/Rank.png");
    ipRankXP.LoadFromFile("Graphics/Player Stats/RankXP.png");
    iCursor.LoadFromFile("Graphics/Cursor.png");

    //SetSmooth()
    ipStr.SetSmooth(false);
    ipDex.SetSmooth(false);
    ipInt.SetSmooth(false);
    ipEnd.SetSmooth(false);
    ipCrit.SetSmooth(false);
    ipSwd.SetSmooth(false);
    ipAxe.SetSmooth(false);
    ipBow.SetSmooth(false);
    ipStar.SetSmooth(false);
    ipWand.SetSmooth(false);
    ipStaff.SetSmooth(false);
    ipSkills.SetSmooth(false);
    ipHealth.SetSmooth(false);
    ipEnergy.SetSmooth(false);
    ipGuard.SetSmooth(false);
    ipNumHP.SetSmooth(false);
    ipNumEP.SetSmooth(false);
    ipRankXP.SetSmooth(false);
    ipRank.SetSmooth(false);
    //SetImage!!
    StatBack.SetImage(iStatBack);
    StatWindow.SetImage(iStatWindow);
    pHealth.SetImage(ipHealth);
    pEnergy.SetImage(ipEnergy);
    pStr.SetImage(ipStr);
    pDex.SetImage(ipDex);
    pInt.SetImage(ipInt);
    pEnd.SetImage(ipEnd);
    pCrit.SetImage(ipCrit);
    pSwd.SetImage(ipSwd);
    pAxe.SetImage(ipAxe);
    pBow.SetImage(ipBow);
    pStar.SetImage(ipStar);
    pWand.SetImage(ipWand);
    pStaff.SetImage(ipStaff);
    pBag.SetImage(ipBag);
    pEquip.SetImage(ipEquip);
    pSkills.SetImage(ipSkills);
    pNumHP.SetImage(ipNumHP);
    pNumEP.SetImage(ipNumEP);
    pGuard.SetImage(ipGuard);
    pRank.SetImage(ipRank);
    pRankXP.SetImage(ipRankXP);
    Cursor.SetImage(iCursor);
    //SetPosition(x,y)!!
    StatBack.SetPosition(0,0);
    StatWindow.SetPosition(-5.f/16.f,-5.f/16.f);
    pHealth.SetPosition(5.f/16.f,23.25f/16.f);
    pEnergy.SetPosition(5.f/16.f,31.5f/16.f);
    pStr.SetPosition(59.f/16.f,23.f/16.f);
    pDex.SetPosition(59.f/16.f,35.f/16.f);
    pInt.SetPosition(59.f/16.f,47.f/16.f);
    pEnd.SetPosition(3.f/16.f,37.f/16.f);
    pCrit.SetPosition(32.f/16.f,37.f/16.f);
    pSwd.SetPosition(63.f/16.f,21.f/16.f);
    pAxe.SetPosition(63.f/16.f,29.f/16.f);
    pBow.SetPosition(63.f/16.f,33.f/16.f);
    pStar.SetPosition(63.f/16.f,41.f/16.f);
    pWand.SetPosition(63.f/16.f,45.f/16.f);
    pStaff.SetPosition(63.f/16.f,53.f/16.f);
    pBag.SetPosition(2.f/16.f,60.f/16.f);
    pEquip.SetPosition(2.f/16.f,60.f/16.f);
    pSkills.SetPosition(71.f/16.f,61.f/16.f);
    pNumHP.SetPosition(4.f/16.f,22.f/16.f);
    pNumEP.SetPosition(4.f/16.f,30.f/16.f);
    pGuard.SetPosition(4.f/16.f,22.5f/16.f);
    pRank.SetPosition(41.5f/16.f,25.f/16.f);
    pRankXP.SetPosition(39.5f/16.f,23.f/16.f);

    //VECTOR STORE
    SpriteList.push_back(StatWindow);
    SpriteList.push_back(pHealth);
    SpriteList.push_back(pEnergy);
    SpriteList.push_back(pStr);
    SpriteList.push_back(pDex);
    SpriteList.push_back(pInt);
    SpriteList.push_back(pEnd);
    SpriteList.push_back(pCrit);
    SpriteList.push_back(pSwd);
    SpriteList.push_back(pAxe);
    SpriteList.push_back(pBow);
    SpriteList.push_back(pStar);
    SpriteList.push_back(pWand);
    SpriteList.push_back(pStaff);
    SpriteList.push_back(pBag);
    SpriteList.push_back(pEquip);
    SpriteList.push_back(pSkills);
    SpriteList.push_back(pNumHP);
    SpriteList.push_back(pNumEP);
    SpriteList.push_back(pGuard);
    SpriteList.push_back(pRank);
    SpriteList.push_back(pRankXP);
    SpriteList.push_back(Cursor);


}


void SFMLdraw()
{
//////////////////////////////STAT RESIZE/SUBRECT///////////////////////////////////////
        SpriteList[1].SetSubRect(sf::IntRect(0,0,120,12)); //30,3
        SpriteList[2].SetSubRect(sf::IntRect(0,0,120,12)); //30,3
        SpriteList[3].SetSubRect(sf::IntRect(pPlayer->get_Str()*28,0,(pPlayer->get_Str()*28)+28,7)); //28,7
        SpriteList[4].SetSubRect(sf::IntRect(pPlayer->get_Dex()*28,0,(pPlayer->get_Dex()*28)+28,7)); //28,7
        SpriteList[5].SetSubRect(sf::IntRect(pPlayer->get_Int()*28,0,(pPlayer->get_Int()*28)+28,7)); //28,7
        SpriteList[6].SetSubRect(sf::IntRect(pPlayer->get_End()*28,0,(pPlayer->get_End()*28)+28,7)); //28,7
        SpriteList[7].SetSubRect(sf::IntRect(pPlayer->get_Crit()*28,0,(pPlayer->get_Crit()*28)+28,7)); //28,7
        SpriteList[8].SetSubRect(sf::IntRect(pPlayer->get_Sword()*18,0,(pPlayer->get_Sword()*18)+18,3)); //18,3
        SpriteList[9].SetSubRect(sf::IntRect(pPlayer->get_Axe()*18,0,(pPlayer->get_Axe()*18)+18,3)); //18,3
        SpriteList[10].SetSubRect(sf::IntRect(pPlayer->get_Bow()*18,0,(pPlayer->get_Bow()*18)+18,3)); //18,3
        SpriteList[11].SetSubRect(sf::IntRect(pPlayer->get_Star()*18,0,(pPlayer->get_Star()*18)+18,3)); //18,3
        SpriteList[12].SetSubRect(sf::IntRect(pPlayer->get_Wand()*18,0,(pPlayer->get_Wand()*18)+18,3)); //18,3
        SpriteList[13].SetSubRect(sf::IntRect(pPlayer->get_Staff()*18,0,(pPlayer->get_Staff()*18)+18,3)); //18,3
        SpriteList[14].SetSubRect(sf::IntRect((pPlayer->get_BagShow()*60)+120,0,(pPlayer->get_BagShow()*60)+180,48));
        SpriteList[15].SetSubRect(sf::IntRect(pPlayer->get_EquipShow()*60,0,(pPlayer->get_EquipShow()*60)+60,48));
        SpriteList[16].SetSubRect(sf::IntRect(pPlayer->get_SkillShow()*30,0,(pPlayer->get_SkillShow()*30)+30,64));
        SpriteList[17].SetSubRect(sf::IntRect(pPlayer->get_Health()*7,0,(pPlayer->get_Health()*7)+7,5));
        SpriteList[18].SetSubRect(sf::IntRect(pPlayer->get_Energy()*7,0,(pPlayer->get_Energy()*7)+7,5));
        SpriteList[19].SetSubRect(sf::IntRect(0,0,128,20));
        SpriteList[20].SetSubRect(sf::IntRect(pPlayer->get_Rank()*14,0,(pPlayer->get_Rank()*14)+14,6));//10
        SpriteList[21].SetSubRect(sf::IntRect(pPlayer->get_tRankXPN()*18,0,(pPlayer->get_tRankXPN()*18)+18,10));//16

/////////////////////RESIZE PART
        SpriteList[0].Resize(410.f/16.f,310.f/16.f);
        SpriteList[1].Resize(pPlayer->get_tHealth()/64.f,12.f/64.f);
        SpriteList[2].Resize(pPlayer->get_tEnergy()/64.f,12.f/64.f);
        SpriteList[3].Resize(28.f/16.f,7.f/16.f);
        SpriteList[4].Resize(28.f/16.f,7.f/16.f);
        SpriteList[5].Resize(28.f/16.f,7.f/16.f);
        SpriteList[6].Resize(28.f/16.f,7.f/16.f);
        SpriteList[7].Resize(28.f/16.f,7.f/16.f);
        SpriteList[8].Resize(18.f/16.f,3.f/16.f);
        SpriteList[9].Resize(18.f/16.f,3.f/16.f);
        SpriteList[10].Resize(18.f/16.f,3.f/16.f);
        SpriteList[11].Resize(18.f/16.f,3.f/16.f);
        SpriteList[12].Resize(18.f/16.f,3.f/16.f);
        SpriteList[13].Resize(18.f/16.f,3.f/16.f);
        SpriteList[14].Resize(60.f/16.f,48.f/16.f);
        SpriteList[15].Resize(60.f/16.f,48.f/16.f);
        SpriteList[16].Resize(30.f/16.f,64.f/16.f);
        SpriteList[17].Resize(7.f/16.f,5.f/16.f);
        SpriteList[18].Resize(7.f/16.f,5.f/16.f);
        SpriteList[19].Resize(pPlayer->get_tGuard()/64.f,20.f/64.f);
        SpriteList[20].Resize(14.f/16.f,6.f/16.f);
        SpriteList[21].Resize(18.f/16.f,10.f/16.f);
        SpriteList[22].Resize(15.f/16.f,15.f/16.f);


///////////////////////////////////END RESIZE/SUBRECT!!!////////////////////////////////
////////////////////////////////////DONT TOUCH/////////////////////////////////////////

///////////////////////////////NOW YOU CAN TOUCH//////////////////////////////////////////
//////////////////////////////DRAW STARTS///////////////////////////////////////////////
        GameWind.Draw(SpriteList[0]);
        GameWind.Draw(SpriteList[19]);
        GameWind.Draw(SpriteList[1]);
        GameWind.Draw(SpriteList[17]);
        GameWind.Draw(SpriteList[2]);
        GameWind.Draw(SpriteList[18]);
        GameWind.Draw(SpriteList[3]);
        GameWind.Draw(SpriteList[4]);
        GameWind.Draw(SpriteList[5]);
        GameWind.Draw(SpriteList[6]);
        GameWind.Draw(SpriteList[7]);
        GameWind.Draw(SpriteList[8]);
        GameWind.Draw(SpriteList[9]);
        GameWind.Draw(SpriteList[10]);
        GameWind.Draw(SpriteList[11]);
        GameWind.Draw(SpriteList[12]);
        GameWind.Draw(SpriteList[13]);
        GameWind.Draw(SpriteList[14]);
        GameWind.Draw(SpriteList[15]);
}


void GLMcreate()
{
    GLMmodel* World = glmReadOBJ("3Dobject/WorldMap3Dv1.obj");
    glmUnitize(World);
    glmScale(World,1);
}


void GLdraw()
{
    GameWind.SetActive();
    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
    ////////AMBIENT LIGHT
    GLfloat AmbientColor[] = {0.05f,0.05f,0.2f,1.0f};
    glLightModelfv(GL_LIGHT_MODEL_AMBIENT,AmbientColor);
    ////////POSITIONED LIGHT
    GLfloat LightColor0[] = {0.5f,0.5f,0.5f,1.0f};
    GLfloat LightPos0[] = {4.0f,4.0f,0.0f,1.0f};
    glLightfv(GL_LIGHT0,GL_DIFFUSE,LightColor0);
    glLightfv(GL_LIGHT0,GL_POSITION,LightPos0);
    ////////DIRECTED LIGHT
    GLfloat LightColor1[] = {0.9f,0.9f,0.6f,1.0f};
    /////Coming from direction (x,y,z)
    GLfloat LightPos1[] = {-1.0f,0.5f,0.5f,0.0f};
    glLightfv(GL_LIGHT1,GL_DIFFUSE,LightColor1);
    glLightfv(GL_LIGHT1,GL_POSITION,LightPos1);


    ///DRAWING MODELS
}


void GLiniti()
{
    GameWind.PreserveOpenGLStates(true);
    GameWind.ShowMouseCursor(false);

    glClearDepth(1.f);
    glClearColor(0.2f,0.2f,0.8f,1.f);
    /////z buffer
    glEnable(GL_POLYGON_STIPPLE);
    glEnable(GL_BLEND);
    glEnable(GL_DEPTH_TEST);
    glEnable(GL_COLOR_MATERIAL);
    glEnable(GL_LIGHTING);
    glEnable(GL_LIGHT0);
    glEnable(GL_CULL_FACE);
    glEnable(GL_LIGHT1);
    glEnable(GL_NORMALIZE);
    glEnable(GL_TEXTURE_2D);

    glEnableClientState(GL_VERTEX_ARRAY);
    glEnableClientState(GL_TEXTURE_COORD_ARRAY);
    glEnableClientState(GL_NORMAL_ARRAY);

    glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
    glCullFace(GL_FRONT);
    glFrontFace(GL_CW);
    glShadeModel(GL_SMOOTH);
    glDepthMask(GL_TRUE);
    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
    glDepthFunc(GL_LEQUAL);


    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluPerspective(50.f,(double)800 / (double)600,200.f,0.f);
    glTranslatef(0.f, 0.f, -10.0f);
}


GLuint LoadTexture(sf::Image image)
{
    GLuint Texture;
    glGenTextures(1, &Texture);
    glBindTexture(GL_TEXTURE_2D, Texture);
    gluBuild2DMipmaps(GL_TEXTURE_2D, GL_RGBA,image.GetWidth(),image.GetHeight(), GL_RGBA, GL_UNSIGNED_BYTE,image.GetPixelsPtr());
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
    return Texture;
}

void ITEMdefault()
{
    Blank *BlankSpot=new Blank();
    BlankSpot->ItemCreate(0,0,0,0,0,0,0);

    ///TEST ITEMS

    Weapon *sword=new Weapon();
    sword->ItemCreate(0,0,0,sf::Randomizer::Random(0,5),1,0,sf::Randomizer::Random(1,4));
    Armor *sword2=new Armor();
    sword2->ItemCreate(0,0,0,sf::Randomizer::Random(0,5),2,0,sf::Randomizer::Random(1,4));
    Necklace *sword3=new Necklace();
    sword3->ItemCreate(0,0,0,sf::Randomizer::Random(0,5),3,0,sf::Randomizer::Random(1,4));
    Consume *hppotion=new Consume();
    hppotion->ItemCreate(0,0,0,6,83,0,6);

    DefItemList.push_back(BlankSpot);
    DefItemList.push_back(sword);
    DefItemList.push_back(sword2);
    DefItemList.push_back(sword3);
    DefItemList.push_back(hppotion);
}

score 1 · Accepted Answer

也没有一种特定的矩阵模式可以切换 OpenGL。我已经在这篇文章OpenGL：什么是 MatrixMode？，我将在这里简单地复制：

OpenGL 使用几个矩阵来转换几何图形和相关数据。这些矩阵是：

模型视图——将对象几何体放置在全局的、未投影的空间中
Proection——将全局坐标投影到剪辑空间中；你可能会认为它是一种镜头
纹理——调整之前的纹理坐标；主要用于实现纹理投影（即像投影仪中的幻灯片一样投影纹理）
颜色——调整顶点颜色。很少接触

所有这些矩阵一直在使用。由于它们遵循所有相同的规则，因此 OpenGL 只有一组矩阵操作函数：glPushMatrix、glPopMatrix、glLoadIdentity、glLoadMatrix、glMultMatrix、glTranslate、glRotate、glScale、glOrtho、glFrustum。

glMatrixMode 选择这些操作作用于哪个矩阵。假设您想编写一些 C++ 命名空间包装器，它可能如下所示：

namespace OpenGL {
  // A single template class for easy OpenGL matrix mode association
  template<GLenum mat> class Matrix
  {
  public:
    void LoadIdentity() const 
        { glMatrixMode(mat); glLoadIdentity(); }

    void Translate(GLfloat x, GLfloat y, GLfloat z) const
        { glMatrixMode(mat); glTranslatef(x,y,z); }
    void Translate(GLdouble x, GLdouble y, GLdouble z) const
        { glMatrixMode(mat); glTranslated(x,y,z); }

    void Rotate(GLfloat angle, GLfloat x, GLfloat y, GLfloat z) const
        { glMatrixMode(mat); glRotatef(angle, x, y, z); }
    void Rotate(GLdouble angle, GLdouble x, GLdouble y, GLdouble z) const
        { glMatrixMode(mat); glRotated(angle, x, y, z); }

    // And all the other matrix manipulation functions
    // using overloading to select proper OpenGL variant depending on
    // function parameters, and all the other C++ whiz.
    // ...
  };

  // 
  const Matrix<GL_MODELVIEW>  Modelview;
  const Matrix<GL_PROJECTION> Projection;
  const Matrix<GL_TEXTURE>    Texture;
  const Matrix<GL_COLOR>      Color;
}

稍后在 C++ 程序中，您可以编写

void draw_something()
{
    OpenGL::Projection::LoadIdentity();
    OpenGL::Projection::Frustum(...);

    OpenGL::Modelview::LoadIdentity();
    OpenGL::Modelview::Translate(...);

    // drawing commands
}

不幸的是，C++ 不能模板命名空间，或者在实例上应用using（或with）（其他语言有这个），否则我会写类似的东西（无效的 C++）

void draw_something_else()
{
    using namespace OpenGL;

    with(Projection) {    // glMatrixMode(GL_PROJECTION);
        LoadIdentity();   // glLoadIdentity();
        Frustum(...);     // glFrustum(...);
    }

    with(Modelview) {     // glMatrixMode(GL_MODELVIEW);
        LoadIdentity();   // glLoadIdentity();
        Translate(...);   // glTranslatef(...);
    }

}

我认为最后一段（伪）代码清楚地表明：glMatrixMode 是withOpenGL 的一种声明。

所有的矩阵都在渲染过程中使用！

score 0 · Accepted Answer

0

You move the camera by using glTranslate().

于 2011-03-21T22:54:29.540 回答

c++ - 使用 GLM 的最佳 glMatrixMode() 是什么？

2 回答 2

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