C++ 设置openGL窗口的背景图像
我试图通过在正交投影矩阵上创建一个四边形并向其添加纹理来设置openGL窗口的背景图像。我还在我的应用程序中使用GLUT工具包 然而,我有几个问题。下面是说明问题的屏幕截图:图像是灰度的,它在x和y上重复,即使纹理大小设置为与四边形相同 这就是我努力实现的目标: 这就是我得到的: 渲染和加载纹理的代码如下所示:C++ 设置openGL窗口的背景图像,c++,opengl,graphics,glut,C++,Opengl,Graphics,Glut,我试图通过在正交投影矩阵上创建一个四边形并向其添加纹理来设置openGL窗口的背景图像。我还在我的应用程序中使用GLUT工具包 然而,我有几个问题。下面是说明问题的屏幕截图:图像是灰度的,它在x和y上重复,即使纹理大小设置为与四边形相同 这就是我努力实现的目标: 这就是我得到的: 渲染和加载纹理的代码如下所示: void orthogonalStart (void) { glMatrixMode(GL_PROJECTION); glPushMatrix(); glLo
void orthogonalStart (void) {
glMatrixMode(GL_PROJECTION);
glPushMatrix();
glLoadIdentity();
gluOrtho2D(0, w1, 0, h1);
glScalef(1, -1, 1);
glTranslatef(0, -h1, 0);
glMatrixMode(GL_MODELVIEW);
}
void orthogonalEnd (void) {
glMatrixMode(GL_PROJECTION);
glPopMatrix();
glMatrixMode(GL_MODELVIEW);
}
GLuint LoadTexture( const char * filename, int width, int height )
{
GLuint texture;
unsigned char * data;
FILE * file;
//The following code will read in our RAW file
file = fopen( filename, "rb" );
if ( file == NULL ) return 0;
data = (unsigned char *)malloc( width * height * 3 );
fread( data, width * height * 3, 1, file );
fclose( file );
glGenTextures( 1, &texture );
glBindTexture( GL_TEXTURE_2D, texture );
glTexEnvf( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE );
//even better quality, but this will do for now.
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,GL_LINEAR );
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER,GL_LINEAR );
//to the edge of our shape.
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT );
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT );
//Generate the texture
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0,GL_RGB, GL_UNSIGNED_BYTE, data);
free( data ); //free the texture
return texture; //return whether it was successful
}
void FreeTexture( GLuint texture )
{
glDeleteTextures( 1, &texture );
}
void background (void) {
glBindTexture( GL_TEXTURE_2D, texture );
orthogonalStart();
glBegin(GL_QUADS);
glTexCoord2d(0.0,0.0); glVertex2f(0, 0);
glTexCoord2d(1.0,0.0); glVertex2f(1024, 0);
glTexCoord2d(1.0,1.0); glVertex2f(1024, 1024);
glTexCoord2d(0.0,1.0); glVertex2f(0, 1024);
glEnd();
orthogonalEnd();
}
void display (void) {
glClearColor (1.0,0.0,0.0,1.0);
glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity();
glEnable( GL_TEXTURE_2D );
background();
gluLookAt (0.0, 0.0, 5.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);
glutSwapBuffers();
}
为了将纹理从png转换成原始格式,我使用photoshop,所以我认为灰度图像可能是由于转换
注意:我刚刚开始学习open,所以这可能不是最好的方法。如果有更好的办法,请告诉我
编辑:图像必须保留在一个位置,而不是重新缩放我想要的投影矩阵
此外,如果正在进行3分量像素,则将纹理加载的GL\u UNPACK\u ALIGNMENT
设置为1:
#include <GL/glut.h>
int w1 = 0;
int h1 = 0;
void reshape(int w, int h)
{
w1 = w;
h1 = h;
glViewport(0, 0, w, h);
}
void orthogonalStart()
{
glMatrixMode(GL_PROJECTION);
glPushMatrix();
glLoadIdentity();
gluOrtho2D(-w1/2, w1/2, -h1/2, h1/2);
glMatrixMode(GL_MODELVIEW);
}
void orthogonalEnd()
{
glMatrixMode(GL_PROJECTION);
glPopMatrix();
glMatrixMode(GL_MODELVIEW);
}
GLuint texture = 0;
void background()
{
glBindTexture( GL_TEXTURE_2D, texture );
orthogonalStart();
// texture width/height
const int iw = 500;
const int ih = 500;
glPushMatrix();
glTranslatef( -iw/2, -ih/2, 0 );
glBegin(GL_QUADS);
glTexCoord2i(0,0); glVertex2i(0, 0);
glTexCoord2i(1,0); glVertex2i(iw, 0);
glTexCoord2i(1,1); glVertex2i(iw, ih);
glTexCoord2i(0,1); glVertex2i(0, ih);
glEnd();
glPopMatrix();
orthogonalEnd();
}
void display()
{
glClearColor (1.0,0.0,0.0,1.0);
glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity();
glEnable( GL_TEXTURE_2D );
background();
gluLookAt (0.0, 0.0, 5.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);
glutSwapBuffers();
}
GLuint LoadTexture()
{
unsigned char data[] = { 255,0,0, 0,255,0, 0,0,255, 255,255,255 };
glGenTextures( 1, &texture );
glBindTexture( GL_TEXTURE_2D, texture );
glPixelStorei( GL_UNPACK_ALIGNMENT, 1 );
glTexEnvf( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE );
//even better quality, but this will do for now.
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,GL_NEAREST);
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER,GL_NEAREST);
//to the edge of our shape.
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT );
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT );
//Generate the texture
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, 2, 2, 0,GL_RGB, GL_UNSIGNED_BYTE, data);
return texture; //return whether it was successful
}
int main(int argc, char **argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGBA | GLUT_DEPTH | GLUT_DOUBLE);
glutInitWindowSize(800,600);
glutCreateWindow("Aspect Ratio");
glutDisplayFunc(display);
glutReshapeFunc(reshape);
texture = LoadTexture();
glutMainLoop();
return 0;
}
#包括
int w1=0;
int h1=0;
空洞重塑(整数w,整数h)
{
w1=w;
h1=h;
glViewport(0,0,w,h);
}
void正交开始()
{
glMatrixMode(GL_投影);
glPushMatrix();
glLoadIdentity();
gluOrtho2D(-w1/2,w1/2,-h1/2,h1/2);
glMatrixMode(GLU模型视图);
}
void正交结束()
{
glMatrixMode(GL_投影);
glPopMatrix();
glMatrixMode(GLU模型视图);
}
胶合纹理=0;
无效背景()
{
glBindTexture(GL_TEXTURE_2D,纹理);
正交开始();
//纹理宽度/高度
常数int iw=500;
常数int ih=500;
glPushMatrix();
glTranslatef(-iw/2,-ih/2,0);
glBegin(GL_QUADS);
glTexCoord2i(0,0);glVertex2i(0,0);
glTexCoord2i(1,0);glVertex2i(iw,0);
glTexCoord2i(1,1);glVertex2i(iw,ih);
glTexCoord2i(0,1);glVertex2i(0,ih);
格伦德();
glPopMatrix();
正交端();
}
无效显示()
{
glClearColor(1.0,0.0,0.0,1.0);
glClear(GL_颜色_缓冲_位| GL_深度_缓冲_位);
glLoadIdentity();
glEnable(GL_纹理_2D);
背景();
gluLookAt(0.0,0.0,5.0,0.0,0.0,0.0,0.0,1.0,0.0);
glutSwapBuffers();
}
GLuint LoadTexture()
{
无符号字符数据[]={255,0,0,0255,0,0,0255,255255};
glGenTextures(1,&纹理);
glBindTexture(GL_TEXTURE_2D,纹理);
glPixelStorei(GLU解包对齐,1);
glTexEnvf(GL_纹理_环境,GL_纹理_环境模式,GL_调制);
//甚至更好的质量,但现在就可以了。
glTexParameterf(GL_纹理2D,GL_纹理最小过滤器,GL_最近);
glTexParameterf(GL_纹理2D,GL_纹理MAG_过滤器,GL_最近);
//到我们形状的边缘。
glTexParameterf(GL_纹理2D、GL_纹理包裹S、GL_重复);
glTexParameterf(GL_纹理、GL_纹理、GL_包裹、GL_重复);
//生成纹理
GLTEXAGE2D(GL_纹理_2D,0,GL_RGB,2,2,0,GL_RGB,GL_无符号_字节,数据);
return texture;//返回是否成功
}
int main(int argc,字符**argv)
{
glutInit(&argc,argv);
glutInitDisplayMode(GLUT_RGBA | GLUT_深度| GLUT_双精度);
glutInitWindowSize(800600);
窗口(“纵横比”);
glutDisplayFunc(显示器);
GLUTREFORUNC(重塑);
纹理=加载纹理();
glutMainLoop();
返回0;
}
旁注:我想你指的是glTexCoord2f(“d”代表“双重”,而不是“维度”)。@Marcelocontos是的,但这可能不会有什么不同,不是吗?不,我不认为这会影响结果。