int main(int argc, const char * argv[]) {
if( !glfwInit() ) {
cerr << "Unable to initialize glfw" << endl;
return false;
}
/* Tell GLFW to use OpenGL 4.1 */
glfwWindowHint( GLFW_CONTEXT_VERSION_MAJOR, 4 );
glfwWindowHint( GLFW_CONTEXT_VERSION_MINOR, 1 );
glfwWindowHint( GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE );
glfwWindowHint( GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE );
GLFWwindow * window = glfwCreateWindow( WINDOW_WIDTH, WINDOW_HEIGHT, "Arcball", NULL, NULL );
if ( !window ) {
cerr << "Unable to create glfw window" << endl;
glfwTerminate();
return false;
}
glfwMakeContextCurrent( window );
glfwSetInputMode( window, GLFW_STICKY_KEYS, GL_TRUE );
cout << "OpenGL Ver: " << glGetString( GL_VERSION ) << endl;
glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
glShadeModel( GL_SMOOTH );
glEnable( GL_DEPTH_TEST );
glDepthFunc( GL_LESS );
glFrontFace( GL_CCW );
glEnable( GL_CULL_FACE );
glCullFace( GL_BACK );
/* Set the callback functions */
glfwSetErrorCallback( errorCallback );
glfwSetScrollCallback( window, scrollCallback );
glfwSetKeyCallback( window, keyCallback );
glfwSetFramebufferSizeCallback( window, frameBufferSizeCallback );
glfwSetCursorPosCallback( window, cursorCallback );
glfwSetMouseButtonCallback( window, mouseButtonCallback );
GLuint vertex_array_id;
glGenVertexArrays( 1, &vertex_array_id );
glBindVertexArray( vertex_array_id );
Shader shader( "simpleLighting.vsh", "simpleLighting.fsh" );
GLuint cube_buffers[2];
glGenBuffers( 2, cube_buffers );
glBindBuffer( GL_ARRAY_BUFFER, cube_buffers[0] );
glBufferData( GL_ARRAY_BUFFER, sizeof(glm::vec3) * cube_buffer_data.size(), &cube_buffer_data[0], GL_STATIC_DRAW );
glBindBuffer( GL_ARRAY_BUFFER, cube_buffers[1] );
glBufferData( GL_ARRAY_BUFFER, sizeof(glm::vec3) * cube_normals_data.size(), &cube_normals_data[0], GL_STATIC_DRAW );
GLuint floor_buffers[2];
glGenBuffers( 2, floor_buffers );
glBindBuffer( GL_ARRAY_BUFFER, floor_buffers[0] );
glBufferData( GL_ARRAY_BUFFER, sizeof(glm::vec3) * floor_buffer_data.size(), &floor_buffer_data[0], GL_STATIC_DRAW );
glBindBuffer( GL_ARRAY_BUFFER, floor_buffers[1] );
glBufferData( GL_ARRAY_BUFFER, sizeof(glm::vec3) * floor_normals_data.size(), &floor_normals_data[0], GL_STATIC_DRAW );
glm::mat4 model = glm::mat4(1.0);
glm::mat4 view = glm::lookAt( glm::vec3(0.0f, 0.0f, 3.0f), glm::vec3(0., 0., 0.), glm::vec3(0., 1., 0.) );
glm::mat4 projection = glm::perspective(70.0f, 4.0f/3.0f, 0.1f, 100.0f );
glm::vec3 light_position = glm::vec3( 4, 4, 4 );
shader.bind();
shader.setUniform( "light_position_w", light_position );
while( !glfwWindowShouldClose( window )){
glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
{ /* Draw on 1st viewport, show rotation of the camera */
glViewport( 0, 0, WINDOW_WIDTH / 2, WINDOW_HEIGHT );
glm::mat4 rotated_view = view * arcball.createViewRotationMatrix();
glm::mat4 mvp = projection * rotated_view * model;
shader.setUniform( "light_color", glm::vec3(1.0, 1.0, 0.0) );
shader.setUniform( "v", rotated_view );
shader.setUniform( "m", model );
shader.setUniform( "mvp", mvp );
/* Draw cube */
glEnableVertexAttribArray( 0 );
glBindBuffer( GL_ARRAY_BUFFER, cube_buffers[0] );
glVertexAttribPointer( 0, 3, GL_FLOAT, GL_FALSE, 0, (void*) 0 );
glEnableVertexAttribArray( 1 );
glBindBuffer( GL_ARRAY_BUFFER, cube_buffers[1] );
glVertexAttribPointer( 1, 3, GL_FLOAT, GL_FALSE, 0, (void*) 0 );
glEnable( GL_CULL_FACE );
glDrawArrays( GL_TRIANGLE_STRIP, 0, static_cast<int>(cube_buffer_data.size()) );
/* Draw the floor, with different color */
shader.setUniform( "light_color", glm::vec3(0.0, 1.0, 1.0) );
glEnableVertexAttribArray( 0 );
glBindBuffer( GL_ARRAY_BUFFER, floor_buffers[0] );
glVertexAttribPointer( 0, 3, GL_FLOAT, GL_FALSE, 0, (void*) 0 );
glEnableVertexAttribArray( 1 );
glBindBuffer( GL_ARRAY_BUFFER, floor_buffers[1] );
glVertexAttribPointer( 1, 3, GL_FLOAT, GL_FALSE, 0, (void*) 0 );
glDisable( GL_CULL_FACE );
glDrawArrays( GL_TRIANGLE_STRIP, 0, static_cast<int>(floor_buffer_data.size()) );
}
{ /* Draw on 2nd viewport, show rotation of the model */
glViewport( WINDOW_WIDTH / 2, 0, WINDOW_WIDTH / 2, WINDOW_HEIGHT );
glm::mat4 rotated_model = model * arcball.createModelRotationMatrix( view );
glm::mat4 mvp = projection * view * rotated_model;
shader.setUniform( "light_color", glm::vec3(1.0, 1.0, 0.0) );
shader.setUniform( "v", view );
shader.setUniform( "m", rotated_model );
shader.setUniform( "mvp", mvp );
/* Draw cube */
glEnableVertexAttribArray( 0 );
glBindBuffer( GL_ARRAY_BUFFER, cube_buffers[0] );
glVertexAttribPointer( 0, 3, GL_FLOAT, GL_FALSE, 0, (void*) 0 );
glEnableVertexAttribArray( 1 );
glBindBuffer( GL_ARRAY_BUFFER, cube_buffers[1] );
glVertexAttribPointer( 1, 3, GL_FLOAT, GL_FALSE, 0, (void*) 0 );
glEnable( GL_CULL_FACE );
glDrawArrays( GL_TRIANGLE_STRIP, 0, static_cast<int>(cube_buffer_data.size()) );
/* Draw the floor, with different color */
shader.setUniform( "light_color", glm::vec3(0.0, 1.0, 1.0) );
glEnableVertexAttribArray( 0 );
glBindBuffer( GL_ARRAY_BUFFER, floor_buffers[0] );
glVertexAttribPointer( 0, 3, GL_FLOAT, GL_FALSE, 0, (void*) 0 );
glEnableVertexAttribArray( 1 );
glBindBuffer( GL_ARRAY_BUFFER, floor_buffers[1] );
glVertexAttribPointer( 1, 3, GL_FLOAT, GL_FALSE, 0, (void*) 0 );
glDisable( GL_CULL_FACE );
glDrawArrays( GL_TRIANGLE_STRIP, 0, static_cast<int>(floor_buffer_data.size()) );
}
glfwSwapBuffers( window );
glfwPollEvents();
}
shader.unbind();
glDeleteBuffers( 2, cube_buffers );
glDeleteBuffers( 2, floor_buffers );
glDeleteVertexArrays( 1, &vertex_array_id );
return 0;
}
