#include
#include
#include
#include
int main()
{
auto getInstance = []()
{
return (HINSTANCE)GetModuleHandle(nullptr);
};
auto debug = [](GLenum source, GLenum type, GLuint id, GLenum severity, GLsizei length, const GLchar* message, const void* userParam)
{
std::cout << message << std::endl;
};
const char* vsource =
"#version 330 core\n"
"layout(location=0)in vec3 a_position;"
"void main()"
"{gl_Position = vec4(a_position,1.0);}";
const char* fsource =
"#version 330 core\n"
"out vec4 o_color;"
"void main()"
"{o_color = vec4(0.0,0.0,1.0,1.0);}";
const float ver[] =
{
0.0f,0.5f,0.0f,
-0.5f,-0.5f,0.0f,
0.5f,-0.5f,0.0,
};
sf::RenderWindow main_window(sf::VideoMode(640,480),"Multi Contexts");
sf::Event main_event;
sf::WindowHandle main_handle = main_window.getSystemHandle();
HWND sub_window_handle_1 = CreateWindowEx(WS_EX_WINDOWEDGE,TEXT("static"),TEXT(""),WS_VISIBLE|WS_CHILD,0,0,320,480,main_handle,nullptr,getInstance(),nullptr);
sf::RenderWindow sub_window_1(sub_window_handle_1);
sf::ContextSettings cs(8,8,8,3,3,sf::ContextSettings::Attribute::Core|sf::ContextSettings::Attribute::Debug);
HWND sub_window_handle_2 = CreateWindowEx(WS_EX_WINDOWEDGE,TEXT("static"),TEXT(""),WS_VISIBLE|WS_CHILD,320,0,320,480,main_handle,nullptr,getInstance(),nullptr);
sf::RenderWindow sub_window_2(sub_window_handle_2,cs);
sub_window_2.setActive(true);
std::cout << (glewInit() == GLEW_OK) << std::endl;
glDebugMessageCallback(debug,nullptr);
GLuint vs = glCreateShader(GL_VERTEX_SHADER);
GLuint fs = glCreateShader(GL_FRAGMENT_SHADER);
glShaderSource(vs,1,&vsource,nullptr);
glShaderSource(fs,1,&fsource,nullptr);
glCompileShader(vs);
glCompileShader(fs);
GLuint program = glCreateProgram();
glAttachShader(program,vs);
glAttachShader(program,fs);
glLinkProgram(program);
glDeleteShader(vs);
glDeleteShader(fs);
GLuint vao;
glGenVertexArrays(1,&vao);
glBindVertexArray(vao);
GLuint vbo;
glGenBuffers(1,&vbo);
glBindBuffer(GL_ARRAY_BUFFER,vbo);
glBufferData(GL_ARRAY_BUFFER,sizeof(ver),ver,GL_STATIC_DRAW);
glEnableVertexAttribArray(0);
glVertexAttribPointer(0,3,GL_FLOAT,GL_FALSE,3 * sizeof(float),nullptr);
glBindVertexArray(0);
glBindBuffer(GL_ARRAY_BUFFER,0);
glDeleteBuffers(1,&vbo);
//sub_window_2.setActive(false);
sf::RectangleShape rect(sf::Vector2f(160,240));
rect.setFillColor(sf::Color::Red);
rect.setPosition(sf::Vector2f(80,120));
while(main_window.isOpen())
{
while (main_window.pollEvent(main_event))
{
if(main_event.type == sf::Event::Closed)
{
main_window.close();
}
else if(main_event.type == sf::Event::KeyPressed)
{
if(main_event.key.code == sf::Keyboard::Key::Escape)
{
main_window.close();
}
}
}
/*main_window.clear();
main_window.display();*/
sub_window_1.clear();
sub_window_1.draw(rect);
sub_window_1.display();
sub_window_2.setActive(true);
glClear(GL_COLOR_BUFFER_BIT);
glUseProgram(program);
glBindVertexArray(vao);
glDrawArrays(GL_TRIANGLES,0,3);
glBindVertexArray(0);
sub_window_2.setActive(false);
sub_window_2.display();
}
sub_window_2.setActive(true);
glDeleteVertexArrays(1,&vao);
glDeleteProgram(program);
sub_window_2.setActive(false);
return 0;
}
这里创建了一个主窗口(main_window),之后再主窗口内创建了两个小窗口(sub_window),一个是用默认上下文的,另一个是OpenGL3.3的上下文。
窗口创建可以看[C++] [SFML] 基于Win32的SFML程序。
但是最后出现了奇怪的日志,表示没法启用上下文,让人困惑
Failed to activate OpenGL context:
Failed to activate the window’s context
Failed to activate OpenGL context:
Failed to activate the window’s context
Failed to activate OpenGL context:
Failed to activate the window’s context
Failed to activate OpenGL context:
Failed to activate the window’s context
Failed to activate OpenGL context:
Failed to activate the window’s context
Failed to activate OpenGL context:
Failed to activate OpenGL context: