我正在尝试在屏幕上绘制图像。我正在使用 PIC 库来获取图像。
现在，我有一个像素强度数组，每个值看起来像这样
currentImage->pix[currentRow * x * bytesPerPixel] = number from 0 to 256.
我正在尝试使用以下方式绘制图像：
// initialize the most basic image
for (int y = currentImage->ny; y >= 0; y--) {
// draw out each row of pixels
// line 18 -- this following line throws the error on compile
glReadPixels(0, 479-y, 640, 1, GL_RGB, GL_UNSIGNED_BYTE, &image->pix[y*image->nx*image->bpp]);
}
但这不起作用。当我尝试编译时，我不断收到此错误：
g++ -O3 -I/usr/local/src/pic -Iinclude -o current src/main.cpp src/modules/*.cpp -L/usr/local/src/pic -framework OpenGL -framework GLUT -lpicio -ljpeg
src/modules/application.cpp: In function ‘void application::idle()’:
src/modules/application.cpp:18: error: invalid conversion from ‘int’ to ‘const GLvoid*’
make: *** [all] Error 1
以前有没有人遇到过类似的问题？我现在只是尝试在屏幕上绘制最基本的图像。
这是我初始化 gl 显示函数的 main.cpp 函数。
// set up the main display function
glutDisplayFunc(application::display);
// set the various callbacks for the interaction with opengl
glutIdleFunc(application::display);
Application.cpp 完整文件：
namespace application {
void init() {
idle();
}
// implement idle function -- responsible for working with the image on a consistent basis to continually ensure its integrity
void idle() {
// initialize the most basic image
for (int y = currentImage->ny; y >= 0; y--) {
// draw out each row of pixels
glDrawPixels(currentImage->nx, 1, GL_RGBA, GL_UNSIGNED_BYTE, currentImage->pix[y * currentImage->nx * currentImage->bpp]);
}
}
// display is for drawing out the elements using our scaled frame etc
void display() {
// rotate, scaling and translation should take place before this code in the future
// draw a quick cube around the origin of the screen
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glClearColor(000.0, 0.0, 0.0, 1.0);
glutSwapBuffers();
}
}