OpenGL notes (2)

/*-* Opengl Demo Test * * fredric:2016-7-10*/#include<GLUT/GLUT.h>#include<stdlib.h>voiddisplay_demo01 ();voidDisplay_demo1_idle ();intMainintargcConst Char*argv[]) {Glutinit (&argc, argv); Glutcreatewindow ("Fredric Practice Demo");        Glutdisplayfunc (DISPLAY_DEMO01); /** void Apientry glutidlefunc (void (*func) (void)) * Global callback function when no window event occurs*/Glutidlefunc (&display_demo1_idle);    Glutmainloop (); }//****************************************************************************Static intG_angle =0;/** Basic animation and Lighting effects * Four light source models in 3D graphics: * 1, point light Source: light source from a certain point in all directions, such as the sun * 2, Infinity Light Source: For the irradiated object, light parallel intake, such as infinity of sunlight; * 3, directional light: In a certain direction at a specific angle Internal intake, such as flashlights, lights, etc. * 4, ambient light: from all angles have projected into the scene of Light * PS: In OpenGL also consider the light source of their own light * * Light will be attenuated with the increase in distance, the degree of attenuation becomes the attenuation factor K, the directional light source in the direction of deviation will also decay * at the same time   Materials need to consider reflection in the light, divided into: * 1, slow reflection: light emitted into the object, its reflection is in any direction; * 2, specular reflection: the light is emitted to the object, its reflection is based on the normal direction of the irradiated object; * * In general, a 3D image vertex in OpenGL is drawn based on the following formula: * Vertex color = material Spontaneous light color item +∑ (ambient light color + attenuation factor X (Diffuse item + specular item))*/voiddisplay_demo01 () {glclear (Gl_color_buffer_bit|gl_depth_buffer_bit);            Glshademodel (Gl_smooth);            Glmatrixmode (gl_projection);            Glloadidentity (); Gluperspective ( the,1,1, +);            Glmatrixmode (Gl_modelview);            Glloadidentity (); Glulookat (0, - -, $,0, -,Ten,0,0,1); glcolor3f (0.0f,0.4f,0.2f); Glrotatef (-(G_angle *10.0f),10.0f,5.0f,0.0f); //Set the light{glfloat light_position[]= {200.0f,300.0f,400.0f,1.0f}; Glfloat light_ambient[]= {1.0f,1.0f,1.0f,1.0f}; Glfloat light_diffuse[]= {1.0f,1.0f,1.0f,1.0f}; Glfloat light_specular[]= {1.0f,1.0f,1.0f,1.0f}; /** GLLIGHTFV (glenum light, glenum pname, const glfloat *params); * Control the position, intensity, color of the light source * Light:gl_light0 indicates that the first light source gl_light1 represents the second light source * Panme: Type of light control * gl_positio         N: Light Source position * Gl_ambient: ambient light intensity in light source * Gl_diffuse: Intensity of scattered light in light source * gl_specular: Intensity of specular reflection light in light source */GLLIGHTFV (gl_light0, gl_position, light_position);        GLLIGHTFV (Gl_light0, gl_ambient, light_ambient);        GLLIGHTFV (Gl_light0, Gl_diffuse, Light_diffuse);                GLLIGHTFV (Gl_light0, Gl_specular, light_specular);        Glenable (GL_LIGHT0);        Glenable (gl_lighting);    Glenable (gl_depth_test); }        //Set Material{glfloat mat_ambient[]= {0.0f,0.5f,0.3f,1.0f}; Glfloat mat_diffuse[]= {0.0f,0.3f,0.2f,1.0f}; Glfloat mat_specular[]= {0.0f,0.8f,0.2f,1.0f}; Glfloat mat_emission[]= {0.5f,0.0f,0.0f,1.0f}; Glfloat mat_shininess=68.0f; /** GLMATERIALFV (glenum face, glenum pname, const glfloat *params) * Set material * Face: positive and negative      * Gl_front: Front * gl_back: Reverse * gl_front_and_back: positive and negative * pname: Material Properties * Gl_ambient: Ambient Color of material * Gl_diffuse: scattering color of material * Gl_specular: Specular color of material * gl_emission: Hair of material Light color * gl_shininess: Specular reflectance index, 0~128 value is smaller and coarser*/GLMATERIALFV (Gl_front, gl_ambient, mat_ambient);        GLMATERIALFV (Gl_front, Gl_diffuse, Mat_diffuse);        GLMATERIALFV (Gl_front, Gl_specular, mat_specular);        GLMATERIALFV (Gl_front, gl_emission, mat_emission);    Glmaterialf (Gl_front, gl_shininess, mat_shininess); }                //Glutsolidsphere (100,30,30);Glutsolidcube ( the);        Glflush ();    Glutswapbuffers (); }//callback functionvoidDisplay_demo1_idle () {G_angle+=1; Display_demo01 ();}

OpenGL notes (2)