无法将 BMP 图像转换为矩形 OpenGL
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【中文标题】无法将 BMP 图像转换为矩形 OpenGL【英文标题】：Can't Get BMP Image into rectangle OpenGL 【发布时间】：2018-12-15 04:47:43 【问题描述】：所以我有一个 3D 坐标系。图中：
所以我试图在矩形上获取一个 bmp 图像以替换字母 A 和 B 以便图像适合矩形，但无论我做什么，图像都是如图中的红色正方形，或图像加载，但其余线条为黑色。如何将图像放在字母 A 和 B 所在的矩形上？
#define UpperBD 80
#define PI 3.1415926
#define Num_pts 10
using namespace std;
float Xe = 200.0f;//100
float Ye = 300.0f;
float Ze = 450.0f;
float Rho = sqrt(pow(Xe,2) + pow(Ye,2) + pow(Ze,2));
float D_focal = 100.0f;
GLuint texture[2];
struct Image
unsigned long sizeX;
unsigned long sizeY;
char *data;
;
typedef struct Image Image;
#define checkImageWidth 64
#define checkImageHeight 64
GLubyte checkImage[checkImageWidth][checkImageHeight][3];
void makeCheckImage(void)
int i, j, c;
for (i = 0; i < checkImageWidth; i++)
for (j = 0; j < checkImageHeight; j++)
c = ((((i&0x8)==0)^((j&0x8)==0)))*255;
checkImage[i][j][0] = (GLubyte) c;
checkImage[i][j][1] = (GLubyte) c;
checkImage[i][j][2] = (GLubyte) c;
int ImageLoad(char *filename, Image *image)
FILE *file;
unsigned long size;
unsigned long i;
unsigned short int planes;
unsigned short int bpp;
char temp;
if ((file = fopen(filename, "rb"))==NULL)
printf("File Not Found : %s\n",filename);
return 0;
fseek(file, 18, SEEK_CUR);
if ((i = fread(&image->sizeX, 4, 1, file)) != 1)
printf("Error reading width from %s.\n", filename);
return 0;
if ((i = fread(&image->sizeY, 4, 1, file)) != 1)
printf("Error reading height from %s.\n", filename);
return 0;
size = image->sizeX * image->sizeY * 3;
if ((fread(&planes, 2, 1, file)) != 1)
printf("Error reading planes from %s.\n", filename);
return 0;
if (planes != 1)
printf("Planes from %s is not 1: %u\n", filename, planes);
return 0;
if ((i = fread(&bpp, 2, 1, file)) != 1)
printf("Error reading bpp from %s.\n", filename);
return 0;
if (bpp != 24)
printf("Bpp from %s is not 24: %u\n", filename, bpp);
return 0;
fseek(file, 24, SEEK_CUR);
image->data = (char *) malloc(size);
if (image->data == NULL)
printf("Error allocating memory for color-corrected image data");
return 0;
if ((i = fread(image->data, size, 1, file)) != 1)
printf("Error reading image data from %s.\n", filename);
return 0;
for (i=0;i<size;i+=3) // reverse all of the colors. (bgr -> rgb)
temp = image->data[i];
image->data[i] = image->data[i+2];
image->data[i+2] = temp;
// we're done.
return 1;
Image * loadTexture()
Image *image1;
// allocate space for texture
image1 = (Image *) malloc(sizeof(Image));
if (image1 == NULL)
printf("Error allocating space for image");
exit(0);
if (!ImageLoad("g.bmp", image1))
exit(1);
return image1;
void myinit(void)
//something in this function is making it not appear properly
// glClearColor (0.5, 0.5, 0.5, 0.0);
// glEnable(GL_DEPTH_TEST);
// glDepthFunc(GL_LESS);
Image *image1 = loadTexture();
if(image1 == NULL)
printf("Image was not returned from loadTexture\n");
exit(0);
// makeCheckImage();
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
// Create Texture
glGenTextures(2, texture);
glBindTexture(GL_TEXTURE_2D, texture[0]);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR); //scale linearly when image smalled than texture
// glTexImage2D(GL_TEXTURE_2D, 0, 3, image1->sizeX, image1->sizeY, 0, GL_RGB, GL_UNSIGNED_BYTE, image1->data);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);
glBindTexture(GL_TEXTURE_2D, texture[1]);
// glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
// glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
// glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
// glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);
// glTexImage2D(GL_TEXTURE_2D, 0, 3, checkImageWidth, checkImageHeight, 0, GL_RGB, GL_UNSIGNED_BYTE,&checkImage[0][0][0]);
glEnable(GL_TEXTURE_2D);
// glShadeModel(GL_FLAT);
typedef struct
float X[UpperBD];
float Y[UpperBD];
float Z[UpperBD];
pworld;
typedef struct
float X[UpperBD];
float Y[UpperBD];
float Z[UpperBD];
pviewer;
typedef struct
float X[UpperBD];
float Y[UpperBD];
pperspective;
typedef struct
float X[UpperBD];
float Y[UpperBD];
pattern2DL;
typedef struct
float X[UpperBD];
float Y[UpperBD];
arrowpoint;
typedef struct
float r[UpperBD], g[UpperBD], b[UpperBD];
pt_diffuse;
void mydisplay()
float p1x=-1.0f, p1y= 0.0f;
float p2x= 1.0f, p2y= 0.0f;
float p3x= 0.0f, p3y= 1.0f;
float p4x= 0.0f, p4y=-1.0f;
glClear(GL_COLOR_BUFFER_BIT);
glLoadIdentity();
pworld world;
pviewer viewer;
pperspective perspective;
pattern2DL letterL;
arrowpoint arrow;
world.X[0] = 0.0; world.Y[0] = 0.0; world.Z[0] = 0.0;
world.X[1] = 50.0; world.Y[1] = 0.0; world.Z[1] = 0.0;
world.X[2] = 0.0; world.Y[2] = 50.0; world.Z[2] = 0.0;
world.X[3] = 0.0; world.Y[3] = 0.0; world.Z[3] = 50.0;
world.X[4] = 60.0; world.Y[4] = -50.0; world.Z[4] = 0.0;
world.X[5] = 60.0; world.Y[5] = 50.0; world.Z[5] = 0.0;
world.X[7] = 60.0; world.Y[7] = -50.0; world.Z[7] = 100.0;
world.X[6] = 60.0; world.Y[6] = 50.0; world.Z[6] = 100.0;
//define 2D pattern letter A
letterL.X[0] = -10.0; letterL.Y[0] = 10.0;
letterL.X[1] = -15.0; letterL.Y[1] = 10.0;
letterL.X[2] = -20.0; letterL.Y[2] = 30.0;
letterL.X[3] = -40.0; letterL.Y[3] = 30.0;
letterL.X[4] = -45.0; letterL.Y[4] = 10.0;
letterL.X[5] = -50.0; letterL.Y[5] = 10.0;
letterL.X[6] = -37.0; letterL.Y[6] = 70.0;
letterL.X[7] = -23.0; letterL.Y[7] = 70.0;
letterL.X[8] = -25.0; letterL.Y[8] = 40.0;
letterL.X[9] = -35.0; letterL.Y[9] = 40.0;
letterL.X[10] = -30.0; letterL.Y[10] = 60.0;
//letter B
letterL.X[11] = 10.0; letterL.Y[11] = 10.0;
letterL.X[12] = 10.0; letterL.Y[12] = 70.0;
letterL.X[13] = 20.0; letterL.Y[13] = 10.0;
letterL.X[14] = 20.0; letterL.Y[14] = 70.0;
letterL.X[15] = 20.0; letterL.Y[15] = 60.0;
letterL.X[16] = 20.0; letterL.Y[16] = 45.0;
letterL.X[17] = 20.0; letterL.Y[17] = 35.0;
letterL.X[18] = 20.0; letterL.Y[18] = 20.0;
letterL.X[19] = 25.0; letterL.Y[19] = 58.0;
letterL.X[20] = 27.0; letterL.Y[20] = 56.0;
letterL.X[21] = 28.0; letterL.Y[21] = 52.0;
letterL.X[22] = 27.0; letterL.Y[22] = 49.0;
letterL.X[23] = 25.0; letterL.Y[23] = 47.0;
letterL.X[24] = 25.0; letterL.Y[24] = 33.0;
letterL.X[25] = 27.0; letterL.Y[25] = 31.0;
letterL.X[26] = 28.0; letterL.Y[26] = 27.0;
letterL.X[27] = 27.0; letterL.Y[27] = 24.0;
letterL.X[28] = 25.0; letterL.Y[28] = 22.0;
letterL.X[29] = 30.0; letterL.Y[29] = 65.0;
letterL.X[30] = 34.0; letterL.Y[30] = 60.0;
letterL.X[31] = 34.0; letterL.Y[31] = 50.0;
letterL.X[32] = 30.0; letterL.Y[32] = 45.0;
letterL.X[33] = 25.0; letterL.Y[33] = 40.0;
letterL.X[34] = 30.0; letterL.Y[34] = 38.0;
letterL.X[35] = 34.0; letterL.Y[35] = 30.0;
letterL.X[36] = 34.0; letterL.Y[36] = 20.0;
letterL.X[37] = 30.0; letterL.Y[37] = 15.0;
arrow.X[0] = 0.0; arrow.Y[0] = 25.0;
arrow.X[1] = 0.0; arrow.Y[1] = 75.0;
arrow.X[2] = 60.0; arrow.Y[2] = 75.0;
arrow.X[3] = 60.0; arrow.Y[3] = 85.0;
arrow.X[4] = 90.0; arrow.Y[4] = 50.0;
arrow.X[5] = 60.0; arrow.Y[5] = 15.0;
arrow.X[6] = 60.0; arrow.Y[6] = 25.0;
arrow.X[7] = 0.0; arrow.Y[7] = 25.0;
arrow.X[8] = 0.0; arrow.Y[8] = 75.0;
arrow.X[9] = 60.0; arrow.Y[9] = 75.0;
arrow.X[10] = 60.0; arrow.Y[10] = 85.0;
arrow.X[11] = 90.0; arrow.Y[11] = 50.0;
arrow.X[12] = 60.0; arrow.Y[12] = 15.0;
arrow.X[13] = 60.0; arrow.Y[13] = 25.0;
//decoration
for(int i = 0; i <= 37; i++)
world.X[8+i] = 60.0;
world.Y[8+i] = letterL.X[i];
world.Z[8+i] = letterL.Y[i];
//arrow
for(int j = 0; j <= 6; j++)
world.X[46+j] = arrow.X[j]-50;//-50
world.Y[46+j] = arrow.Y[j];
world.Z[46+j] = 100.0;//CHANGE TO 150?
for(int k = 0; k <= 6; k++)
world.X[53+k] = arrow.X[k]-50;
world.Y[53+k] = arrow.Y[k];
world.Z[53+k] = 110.0;//CHANGE TO 150?
float sPheta = Ye / sqrt(pow(Xe,2) + pow(Ye,2));
float cPheta = Xe / sqrt(pow(Xe,2) + pow(Ye,2));
float sPhi = sqrt(pow(Xe,2) + pow(Ye,2)) / Rho;
float cPhi = Ze / Rho;
float xMin = 1000.0, xMax = -1000.0;
float yMin = 1000.0, yMax = -1000.0;
world.X[60] = -200.0; world.Y[60]=50.0; world.Z[60]=200.0;//ps
world.X[61] = 0.0; world.Y[61]=0.0; world.Z[61]=0.0;//vector a
world.X[62] = 0.0; world.Y[62]=0.0; world.Z[62]=1.0;//VECTOR N
float tmp = (world.X[62]*(world.X[61]-world.X[60]))
+(world.Y[62]*(world.Y[61]-world.Y[60]))
+(world.Z[62]*(world.Z[61]-world.Z[60]));
cout << tmp;
float lambda = tmp/((world.X[62]*(world.X[60]-world.X[7]))
+(world.Y[62]*(world.Y[60]-world.Y[7]))
+(world.Z[62]*(world.Z[60]-world.Z[7])));
cout << lambda;
float lambda_2 = tmp/((world.X[62]*(world.X[60]-world.X[6]))//MAKE ARROW HIGHER, ABOVE PROJECTION PLANE SQUARE
+(world.Y[62]*(world.Y[60]-world.Y[6]))
+(world.Z[62]*(world.Z[60]-world.Z[6])));
cout << lambda_2;
world.X[63] = world.X[60]+lambda*(world.X[60]-world.X[7]);//interseciton point for p7, X COMP
world.Y[63] = world.Y[60]+lambda*(world.Y[60]-world.Y[7]);//Y COMP
world.Z[63] = 0.0;
world.X[64] = world.X[60]+lambda_2*(world.X[60]-world.X[6]);//interseciton point for p7, X COMP
world.Y[64] = world.Y[60]+lambda_2*(world.Y[60]-world.Y[6]);//Y COMP
world.Z[64] = 0.0;
//for arrow's shade, 46-52
float lambda_arrow1 = tmp/((world.X[62]*(world.X[60]-world.X[46]))
+(world.Y[62]*(world.Y[60]-world.Y[46]))
+(world.Z[62]*(world.Z[60]-world.Z[46])));
float lambda_arrow2 = tmp/((world.X[62]*(world.X[60]-world.X[47]))
+(world.Y[62]*(world.Y[60]-world.Y[47]))
+(world.Z[62]*(world.Z[60]-world.Z[47])));
float lambda_arrow3 = tmp/((world.X[62]*(world.X[60]-world.X[48]))
+(world.Y[62]*(world.Y[60]-world.Y[48]))
+(world.Z[62]*(world.Z[60]-world.Z[48])));
float lambda_arrow4 = tmp/((world.X[62]*(world.X[60]-world.X[49]))
+(world.Y[62]*(world.Y[60]-world.Y[49]))
+(world.Z[62]*(world.Z[60]-world.Z[49])));
float lambda_arrow5 = tmp/((world.X[62]*(world.X[60]-world.X[50]))
+(world.Y[62]*(world.Y[60]-world.Y[50]))
+(world.Z[62]*(world.Z[60]-world.Z[50])));
float lambda_arrow6 = tmp/((world.X[62]*(world.X[60]-world.X[51]))
+(world.Y[62]*(world.Y[60]-world.Y[51]))
+(world.Z[62]*(world.Z[60]-world.Z[51])));
float lambda_arrow7 = tmp/((world.X[62]*(world.X[60]-world.X[52]))
+(world.Y[62]*(world.Y[60]-world.Y[52]))
+(world.Z[62]*(world.Z[60]-world.Z[52])));
world.X[65] = world.X[60]+lambda_arrow1*(world.X[60]-world.X[46]);//interseciton point for p7, X COMP
world.Y[65] = world.Y[60]+lambda_arrow1*(world.Y[60]-world.Y[46]);//Y COMP
world.Z[65] = 0.0;
world.X[66] = world.X[60]+lambda_arrow2*(world.X[60]-world.X[47]);//interseciton point for p7, X COMP
world.Y[66] = world.Y[60]+lambda_arrow2*(world.Y[60]-world.Y[47]);//Y COMP
world.Z[66] = 0.0;
world.X[67] = world.X[60]+lambda_arrow3*(world.X[60]-world.X[48]);//interseciton point for p7, X COMP
world.Y[67] = world.Y[60]+lambda_arrow3*(world.Y[60]-world.Y[48]);//Y COMP
world.Z[67] = 0.0;
world.X[68] = world.X[60]+lambda_arrow4*(world.X[60]-world.X[49]);//interseciton point for p7, X COMP
world.Y[68] = world.Y[60]+lambda_arrow4*(world.Y[60]-world.Y[49]);//Y COMP
world.Z[68] = 0.0;
world.X[69] = world.X[60]+lambda_arrow5*(world.X[60]-world.X[50]);//interseciton point for p7, X COMP
world.Y[69] = world.Y[60]+lambda_arrow5*(world.Y[60]-world.Y[50]);//Y COMP
world.Z[69] = 0.0;
world.X[70] = world.X[60]+lambda_arrow6*(world.X[60]-world.X[51]);//interseciton point for p7, X COMP
world.Y[70] = world.Y[60]+lambda_arrow6*(world.Y[60]-world.Y[51]);//Y COMP
world.Z[70] = 0.0;
world.X[71] = world.X[60]+lambda_arrow7*(world.X[60]-world.X[52]);//interseciton point for p7, X COMP
world.Y[71] = world.Y[60]+lambda_arrow7*(world.Y[60]-world.Y[52]);//Y COMP
world.Z[71] = 0.0;
pt_diffuse diffuse; //diffuse.r[3]
#define Kdr 0.8
#define Kdg 0.0
#define Kdb 0.0
float distance[UpperBD];
for (int i=63; i<=71; i++)
distance[i] = sqrt(pow((world.X[i]-world.X[60]),2)+ //intersect pt p7
pow((world.Y[i]-world.Y[60]),2)+
pow((world.X[i]-world.X[60]),2) );
//--------compute angle---------------------*
float angle[UpperBD], tmp_dotProd[UpperBD], tmp_mag_dotProd[UpperBD];
for (int i=63; i<=71; i++)
tmp_dotProd[i] = world.Z[i]-world.X[60];
std::cout << " tmp_dotProd[i] " << tmp_dotProd[i] << std::endl;
tmp_mag_dotProd[i] = sqrt(pow((world.X[i]-world.X[60]),2)+ //[45] pt light source
pow((world.Y[i]-world.Y[60]),2)+
pow((world.Z[i]-world.Z[60]),2) );
std::cout << " tmp_mag_dotProd[i] 1 " << tmp_mag_dotProd[i] << std::endl;
angle[i] = tmp_dotProd[i]/ tmp_mag_dotProd[i];
std::cout << "angle[i] " << angle[i] << std::endl;
//compute color intensity
diffuse.r[i] = Kdr * angle[i] / pow(distance[i],2) ;
diffuse.g[i] = Kdg * angle[i] / pow(distance[i],2) ;
diffuse.b[i] = Kdb * angle[i] / pow(distance[i],2) ;
for(int i = 0; i < UpperBD; i++)
viewer.X[i] = -sPheta * world.X[i] + cPheta * world.Y[i];
viewer.Y[i] = -cPheta * cPhi * world.X[i]
- cPhi * sPheta * world.Y[i]
+ sPhi * world.Z[i];
viewer.Z[i] = -sPhi * cPheta * world.X[i]
- sPhi * cPheta * world.Y[i]
-cPheta * world.Z[i] + Rho;
// cout << i;
for(int i = 0; i <= UpperBD; i++)
perspective.X[i] = D_focal * viewer.X[i] / viewer.Z[i] ;
perspective.Y[i] = D_focal * viewer.Y[i] / viewer.Z[i] ;
if (perspective.X[i] > xMax) xMax = perspective.X[i];
if (perspective.X[i] < xMin) xMin = perspective.X[i];
if (perspective.Y[i] > yMax) yMax = perspective.Y[i];
if (perspective.Y[i] < yMin) yMin = perspective.Y[i];
for(int i = 0; i <= UpperBD; i++)
if ((xMax-xMin) != 0) perspective.X[i] = perspective.X[i]/(xMax-xMin);
if ((yMax-yMin) != 0) perspective.Y[i] = perspective.Y[i]/(yMax-yMin);
std::cout << i << perspective.X[i] << perspective.Y[i] << std::endl;
glBegin(GL_LINES);
glClear(GL_COLOR_BUFFER_BIT);
glColor3f(1.0, 0.0, 0.0);
glVertex2f(perspective.X[0],perspective.Y[0]);
glVertex2f(perspective.X[1],perspective.Y[1]);
glColor3f(0.0, 1.0, 0.0);
glVertex2f(perspective.X[0],perspective.Y[0]);
glVertex2f(perspective.X[2],perspective.Y[2]);
glColor3f(0.0, 0.0, 1.0);
glVertex2f(perspective.X[0],perspective.Y[0]);
glVertex2f(perspective.X[3],perspective.Y[3]);
glColor3f(1.0, 1.0, 0.0); // projection plane , THE RECTANGLE WITH THE LETTERS
glVertex2f(perspective.X[4],perspective.Y[4]);
glVertex2f(perspective.X[5],perspective.Y[5]);
glVertex2f(perspective.X[4],perspective.Y[4]);
glVertex2f(perspective.X[7],perspective.Y[7]);
glVertex2f(perspective.X[5],perspective.Y[5]);
glVertex2f(perspective.X[6],perspective.Y[6]);
glVertex2f(perspective.X[6],perspective.Y[6]);
glVertex2f(perspective.X[7],perspective.Y[7]);
glEnd();
glColor3f(0.0, 1.0, 0.0); // LETTER A STARTS HERE
glBegin(GL_POLYGON);
glVertex2f(perspective.X[13],perspective.Y[13]);
glVertex2f(perspective.X[12],perspective.Y[12]);
//etc...
glEnd();
glColor3f(0.0, 1.0, 0.0);
glBegin(GL_POLYGON);
glVertex2f(perspective.X[8],perspective.Y[8]);
glVertex2f(perspective.X[15],perspective.Y[15]);
//etc...
glEnd();
glColor3f(0.0, 1.0, 0.0);
glBegin(GL_POLYGON);
glVertex2f(perspective.X[16],perspective.Y[16]);
glVertex2f(perspective.X[17],perspective.Y[17]);
//etc...
glEnd();
glColor3f(0.0, 1.0, 0.0); //LETTER B STARTS HERE
glBegin(GL_POLYGON);
glVertex2f(perspective.X[19],perspective.Y[19]);
glVertex2f(perspective.X[20],perspective.Y[20]);
//etc...
glEnd();
glColor3f(0.0, 1.0, 0.0);
glBegin(GL_LINES);
//
glVertex2f(perspective.X[23],perspective.Y[23]);
glVertex2f(perspective.X[24],perspective.Y[24]);
glVertex2f(perspective.X[25],perspective.Y[25]);
glVertex2f(perspective.X[26],perspective.Y[26]);
glEnd();
glColor3f(0.0, 1.0, 0.0);
glBegin(GL_POLYGON);
glVertex2f(perspective.X[27],perspective.Y[27]);
glVertex2f(perspective.X[28],perspective.Y[28]);
//etc...
glEnd();
glColor3f(0.0, 1.0, 0.0);
glBegin(GL_POLYGON);
glVertex2f(perspective.X[29],perspective.Y[29]);
glVertex2f(perspective.X[30],perspective.Y[30]);
glVertex2f(perspective.X[24],perspective.Y[24]);
glVertex2f(perspective.X[30],perspective.Y[30]);
glVertex2f(perspective.X[40],perspective.Y[40]);
glVertex2f(perspective.X[39],perspective.Y[39]);
glVertex2f(perspective.X[40],perspective.Y[40]);
glVertex2f(perspective.X[41],perspective.Y[41]);
glVertex2f(perspective.X[24],perspective.Y[24]);
glVertex2f(perspective.X[41],perspective.Y[41]);
glEnd();
glColor3f(0.0, 1.0, 0.0);
glBegin(GL_POLYGON);
glVertex2f(perspective.X[24],perspective.Y[24]);
glVertex2f(perspective.X[41],perspective.Y[41]);
glVertex2f(perspective.X[25],perspective.Y[25]);
glVertex2f(perspective.X[32],perspective.Y[32]);
glVertex2f(perspective.X[33],perspective.Y[33]);
glVertex2f(perspective.X[32],perspective.Y[32]);
glVertex2f(perspective.X[33],perspective.Y[33]);
glVertex2f(perspective.X[34],perspective.Y[34]);
glVertex2f(perspective.X[42],perspective.Y[42]);
glVertex2f(perspective.X[41],perspective.Y[41]);
glVertex2f(perspective.X[42],perspective.Y[42]);
glVertex2f(perspective.X[43],perspective.Y[43]);
glEnd();
glColor3f(0.0, 1.0, 0.0);
glBegin(GL_POLYGON);
glVertex2f(perspective.X[35],perspective.Y[35]);
glVertex2f(perspective.X[34],perspective.Y[34]);
glVertex2f(perspective.X[35],perspective.Y[35]);
glVertex2f(perspective.X[36],perspective.Y[36]);
glVertex2f(perspective.X[26],perspective.Y[26]);
glVertex2f(perspective.X[36],perspective.Y[36]);
glVertex2f(perspective.X[44],perspective.Y[44]);
glVertex2f(perspective.X[43],perspective.Y[43]);
glVertex2f(perspective.X[44],perspective.Y[44]);
glVertex2f(perspective.X[45],perspective.Y[45]);
glVertex2f(perspective.X[21],perspective.Y[21]);
glVertex2f(perspective.X[45],perspective.Y[45]);
glEnd();
glColor3f(1.0, 0.0, 0.0);
glBegin(GL_LINES);//3D arrow starts here
glVertex2f(perspective.X[46],perspective.Y[46]);
glVertex2f(perspective.X[47],perspective.Y[47]);
glVertex2f(perspective.X[48],perspective.Y[48]);
glVertex2f(perspective.X[49],perspective.Y[49]);
glVertex2f(perspective.X[50],perspective.Y[50]);
glVertex2f(perspective.X[51],perspective.Y[51]);
glVertex2f(perspective.X[52],perspective.Y[52]);
glVertex2f(perspective.X[51],perspective.Y[51]);
glVertex2f(perspective.X[49],perspective.Y[49]);
glVertex2f(perspective.X[50],perspective.Y[50]);
glVertex2f(perspective.X[48],perspective.Y[48]);
glVertex2f(perspective.X[47],perspective.Y[47]);
//
glVertex2f(perspective.X[52],perspective.Y[52]);
glVertex2f(perspective.X[46],perspective.Y[46]);
glVertex2f(perspective.X[53],perspective.Y[53]);
glVertex2f(perspective.X[54],perspective.Y[54]);
glVertex2f(perspective.X[55],perspective.Y[55]);
glVertex2f(perspective.X[56],perspective.Y[56]);
glVertex2f(perspective.X[57],perspective.Y[57]);
glVertex2f(perspective.X[58],perspective.Y[58]);
glVertex2f(perspective.X[59],perspective.Y[59]);
glVertex2f(perspective.X[58],perspective.Y[58]);
//
glVertex2f(perspective.X[56],perspective.Y[56]);
glVertex2f(perspective.X[57],perspective.Y[57]);
//
glVertex2f(perspective.X[55],perspective.Y[55]);
glVertex2f(perspective.X[54],perspective.Y[54]);
glVertex2f(perspective.X[59],perspective.Y[59]);
glVertex2f(perspective.X[53],perspective.Y[53]);
glVertex2f(perspective.X[46],perspective.Y[46]);
glVertex2f(perspective.X[46+7],perspective.Y[46+7]);
glVertex2f(perspective.X[47],perspective.Y[47]);
glVertex2f(perspective.X[47+7],perspective.Y[47+7]);
glVertex2f(perspective.X[48],perspective.Y[48]);
glVertex2f(perspective.X[48+7],perspective.Y[48+7]);
glVertex2f(perspective.X[49],perspective.Y[49]);
glVertex2f(perspective.X[49+7],perspective.Y[49+7]);
glVertex2f(perspective.X[50],perspective.Y[50]);
glVertex2f(perspective.X[50+7],perspective.Y[50+7]);
glVertex2f(perspective.X[51],perspective.Y[51]);
glVertex2f(perspective.X[51+7],perspective.Y[51+7]);
glEnd();
glColor3f(1.0, 1.0, 0.0);
glBegin(GL_LINES);
glVertex2f(perspective.X[63],perspective.Y[63]);
glVertex2f(perspective.X[64],perspective.Y[64]);
glVertex2f(perspective.X[63],perspective.Y[63]);
glVertex2f(perspective.X[4],perspective.Y[4]);
glVertex2f(perspective.X[64],perspective.Y[64]);
glVertex2f(perspective.X[5],perspective.Y[5]);
glEnd();
glColor3f(1.0, 0.0, 0.0);
glBegin(GL_LINES);
glVertex2f(perspective.X[65],perspective.Y[65]);
glVertex2f(perspective.X[66],perspective.Y[66]);
glVertex2f(perspective.X[67],perspective.Y[67]);
glVertex2f(perspective.X[66],perspective.Y[66]);
glVertex2f(perspective.X[67],perspective.Y[67]);
glVertex2f(perspective.X[68],perspective.Y[68]);
glVertex2f(perspective.X[69],perspective.Y[69]);
glVertex2f(perspective.X[68],perspective.Y[68]);
glVertex2f(perspective.X[69],perspective.Y[69]);
glVertex2f(perspective.X[70],perspective.Y[70]);
glVertex2f(perspective.X[71],perspective.Y[71]);
glVertex2f(perspective.X[70],perspective.Y[70]);
glVertex2f(perspective.X[71],perspective.Y[71]);
glVertex2f(perspective.X[72],perspective.Y[72]);
glEnd();
glBindTexture(GL_TEXTURE_2D, texture[1]);
glBindTexture(GL_TEXTURE_2D, texture[0]);
glBegin(GL_QUADS);
glTexCoord2f(0.0, 0.0);
glVertex3f(0.1, -0.1, 0.0);
glTexCoord2f(0.1, 0.0);
glVertex3f(0.1, 0.1, 0.0);
glTexCoord2f(0.1, 0.1);
glVertex3f(0.241421, 0.1, -0.141421);
glTexCoord2f(0.0, 0.1);
glVertex3f(0.241421, -0.1, -0.141421);
glEnd();
glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
#define display_scaling 200000.0
#define display_shifting 0.2
for (int i=63; i<=71; i++)
float r, g, b;
r = display_scaling*diffuse.r[i]+display_shifting;
g = diffuse.g[i]; b = diffuse.b[i] ;
glColor3f(r, g, b);
std::cout << "display_scaling*diffuse.r[i] " << r << std::endl;
glBegin(GL_POLYGON);
glVertex2f(perspective.X[i],perspective.Y[i]);
glVertex2f(perspective.X[i]+0.1,perspective.Y[i]);
glVertex2f(perspective.X[i]+0.1,perspective.Y[i]+0.1);
glVertex2f(perspective.X[i],perspective.Y[i]+0.1);
glEnd();
glutSwapBuffers();
glFlush();
int main(int argc, char** argv)
glutInit(&argc,argv);
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
glutCreateWindow("lab");
myinit();
glutDisplayFunc(mydisplay);
glutMainLoop();
【问题讨论】：
您对glTexImage2D() 的两次调用都被注释掉了。由于这就是您将纹理上传到 GPU 的方式，因此您可能在取消注释之前不会获得图像。您是否有理由将它们注释掉？
【参考方案1】：
请注意，由glBegin/glEnd 序列绘制，固定函数管道矩阵堆栈和每个顶点光模型的固定函数管道，几十年来已被弃用。
阅读Fixed Function Pipeline 并查看Vertex Specification 和Shader，了解最先进的渲染方式。
glTexImage2D 指定纹理图像。您必须重新激活已注释掉的代码，因为它将图像日期加载到纹理对象的数据点。
OpenGL 是一个状态引擎。如果设置了一个状态，它会一直保持状态，直到它再次被更改。如果你想绘制一个带有纹理的对象，那么你必须在绘制对象之前启用纹理（glEnable( GL_TEXTURE_2D )），然后必须禁用它（glDisable( GL_TEXTURE_2D )）。
如果启用纹理，则默认情况下纹理元素的颜色乘以当前颜色，因为默认情况下纹理环境模式 (GL_TEXTURE_ENV_MODE) 为GL_MODULATE。见glTexEnv。
这会导致纹理纹素的颜色与glColor4f 设置的最后一种颜色“混合”。
在渲染纹理之前设置“白色”颜色，以解决您的问题：
glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
同样，您可以将环境模式更改为GL_REPLACE，而不是：
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
例如
glBindTexture(GL_TEXTURE_2D, texture[0]);
glEnable( GL_TEXTURE_2D );
glColor4f( 1.0f, 1.0f, 1.0f, 1.0f );
glBegin(GL_QUADS);
glTexCoord2f(0.0, 0.0);
glVertex3f(0.1, -0.1, 0.0);
glTexCoord2f(0.1, 0.0);
glVertex3f(0.1, 0.1, 0.0);
glTexCoord2f(0.1, 0.1);
glVertex3f(0.241421, 0.1, -0.141421);
glTexCoord2f(0.0, 0.1);
glVertex3f(0.241421, -0.1, -0.141421);
glEnd();
glDisable( GL_TEXTURE_2D );
【讨论】：
非常感谢，现在颜色很好了，但是我一直遇到的另一个问题是每次运行代码时都输出不正确，请看一下这张图片：ibb.co/s3w4zX4 全部砸烂出于某种原因在一起。以上是关于无法将 BMP 图像转换为矩形 OpenGL的主要内容，如果未能解决你的问题，请参考以下文章