.. index:: single: Using RingOpenGL and RingFreeGLUT for 3D Graphics; Introduction =================================================== Using RingOpenGL and RingFreeGLUT for 3D Graphics =================================================== In this chapter we will learn about using RingOpenGL .. index:: pair: Using RingOpenGL and RingFreeGLUT for 3D Graphics; Samples Source (Authors) Samples Source (Authors) ======================== The samples in this chapter are based on C Tutorials from (1) http://www.lighthouse3d.com/tutorials/glut-tutorial/ (2) http://www.wikihow.com/Make-a-Cube-in-OpenGL .. index:: pair: Using RingOpenGL and RingFreeGLUT for 3D Graphics; What is RingOpenGL? What is RingOpenGL? =================== RingOpenGL contains the Ring binding to the OpenGL library You can learn about OpenGL from : https://www.opengl.org/ RingOpenGL comes with support for the next versions * OpenGL 1.1 * OpenGL 1.2 * OpenGL 1.3 * OpenGL 1.4 * OpenGL 1.5 * OpenGL 2.0 * OpenGL 2.1 * OpenGL 3.0 * OpenGL 3.2 * OpenGL 3.3 * OpenGL 4.0 * OpenGL 4.1 * OpenGL 4.2 * OpenGL 4.3 * OpenGL 4.4 * OpenGL 4.5 * OpenGL 4.6 For example, if you want to use OpenGL 2.1 then load RingOpenGL 2.1 library .. code-block:: ring load "opengl21lib.ring" .. index:: pair: Using RingOpenGL and RingFreeGLUT for 3D Graphics; What is RingFreeGLUT? What is RingFreeGLUT? ===================== RingFreeGLUT contains the Ring binding to the FreeGLUT library You can learn about FreeGLUT from : http://freeglut.sourceforge.net/ To use the RingFreeGLUT library, Just load the library .. code-block:: ring load "freeglut.ring" .. index:: pair: Using RingOpenGL and RingFreeGLUT for 3D Graphics; The First Window using RingFreeGLUT The First Window using RingFreeGLUT =================================== Example: .. code-block:: ring load "freeglut.ring" func main glutInit() glutInitDisplayMode(GLUT_SINGLE) glutInitWindowSize(800, 600) glutInitWindowPosition(100, 10) glutCreateWindow("RingFreeGLUT - Test 1") glutDisplayFunc(:displayCode) glutMainLoop() func displaycode Screen Shot .. image:: freeglutshot1.png :alt: RingFreeGLUT .. index:: pair: Using RingOpenGL and RingFreeGLUT for 3D Graphics; Drawing using RingOpenGL Drawing using RingOpenGL ======================== Example: .. code-block:: ring load "freeglut.ring" load "opengl21lib.ring" func main glutInit() glutInitDisplayMode(GLUT_SINGLE) glutInitWindowSize(800, 600) glutInitWindowPosition(100, 10) glutCreateWindow("RingFreeGLUT - Test 2") glutDisplayFunc(:displayCode) glutMainLoop() func displaycode glClear(GL_COLOR_BUFFER_BIT) glColor3f(0,255,0) glBegin(GL_POLYGON) glVertex3f(0.0, 0.0, 0.0) glVertex3f(0.5, 0.0, 0.0) glVertex3f(0.5, 0.5, 0.0) glVertex3f(0.0, 0.5, 0.0) glEnd() glColor3f(255,0,0) glBegin(GL_POLYGON) glVertex3f(0.0, 0.0, 0.0) glVertex3f(0.5, 0.0, 0.0) glVertex3f(-0.5,- 1, 0.0) glVertex3f(0.0, -1, 0.0) glEnd() glColor3f(0,0,255) glBegin(GL_POLYGON) glVertex3f(0.0, 0.0, 0.0) glVertex3f(-0.5, 0.0, 0.0) glVertex3f(-0.5,- 0.5, 0.0) glVertex3f(0.0, -0.5, 0.0) glEnd() glFlush() Screen Shot .. image:: freeglutshot2.png :alt: RingFreeGLUT .. index:: pair: Using RingOpenGL and RingFreeGLUT for 3D Graphics; The First Triangle The First Triangle ================== Example: .. code-block:: ring load "freeglut.ring" load "opengl21lib.ring" func main glutInit() glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA) glutInitWindowSize(320,320) glutInitWindowPosition(100, 10) glutCreateWindow("RingFreeGLUT - Test 3") glutDisplayFunc(:renderScene) glutMainLoop() func renderScene glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT) glBegin(GL_TRIANGLES) glVertex3f(-0.5,-0.5,0.0) glVertex3f(0.5,0.0,0.0) glVertex3f(0.0,0.5,0.0) glEnd() glutSwapBuffers() Screen Shot .. image:: freeglutshot3.png :alt: RingFreeGLUT .. index:: pair: Using RingOpenGL and RingFreeGLUT for 3D Graphics; Window Resize Event Window Resize Event =================== Example: .. code-block:: ring load "freeglut.ring" load "opengl21lib.ring" func main // init GLUT and create window glutInit() glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA) glutInitWindowPosition(100,100) glutInitWindowSize(320,320) glutCreateWindow("RingFreeGLUT - Test 4") glutDisplayFunc(:renderScene) glutReshapeFunc(:changeSize) glutMainLoop() func renderScene glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT) glBegin(GL_TRIANGLES) glVertex3f(-2,-2,-5.0) glVertex3f(2,0.0,-5.0) glVertex3f(0.0,2,-5.0) glEnd() glutSwapBuffers() func changesize h = glutEventHeight() w = glutEventWidth() // Prevent a divide by zero, when window is too short // (you cant make a window of zero width). if (h = 0) h = 1 ok ratio = w * 1.0 / h // Use the Projection Matrix glMatrixMode(GL_PROJECTION) // Reset Matrix glLoadIdentity() // Set the viewport to be the entire window glViewport(0, 0, w, h) // Set the correct perspective. gluPerspective(45,ratio,1,100) // Get Back to the Modelview glMatrixMode(GL_MODELVIEW) .. index:: pair: Using RingOpenGL and RingFreeGLUT for 3D Graphics; Triangle Rotation Triangle Rotation ================= Example: .. code-block:: ring load "freeglut.ring" load "opengl21lib.ring" angle = 0 func main // init GLUT and create window glutInit() glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA) glutInitWindowPosition(100,100) glutInitWindowSize(320,320) glutCreateWindow("RingFreeGLUT - Test 5") glutDisplayFunc(:renderScene) glutReshapeFunc(:changeSize) glutIdleFunc(:renderScene) glutMainLoop() func renderScene // Clear Color and Depth Buffers glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT) // Reset transformations glLoadIdentity() // Set the camera gluLookAt( 0.0, 0.0, 10.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0) glRotatef(angle, 0.0, 1.0, 0.0) glBegin(GL_TRIANGLES) glVertex3f(-2.0,-2.0, 0.0) glVertex3f( 2.0, 0.0, 0.0) glVertex3f( 0.0, 2.0, 0.0) glEnd() angle+=0.1 glutSwapBuffers(); func changesize h = glutEventHeight() w = glutEventWidth() // Prevent a divide by zero, when window is too short // (you cant make a window of zero width). if (h = 0) h = 1 ok ratio = w * 1.0 / h // Use the Projection Matrix glMatrixMode(GL_PROJECTION) // Reset Matrix glLoadIdentity() // Set the viewport to be the entire window glViewport(0, 0, w, h) // Set the correct perspective. gluPerspective(45,ratio,1,100) // Get Back to the Modelview glMatrixMode(GL_MODELVIEW) Screen Shot .. image:: freeglutshot4.png :alt: RingFreeGLUT .. index:: pair: Using RingOpenGL and RingFreeGLUT for 3D Graphics; Keyboard Events and Colors Keyboard Events and Colors ========================== Example: .. code-block:: ring load "freeglut.ring" load "opengl21lib.ring" angle = 0 red=1.0 blue=1.0 green=1.0 func main // init GLUT and create window glutInit() glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA) glutInitWindowPosition(100,100) glutInitWindowSize(320,320) glutCreateWindow("RingFreeGLUT - Test 6") glutDisplayFunc(:renderScene) glutReshapeFunc(:changeSize) glutIdleFunc(:renderScene) // here are the new entries glutKeyboardFunc(:processNormalKeys) glutSpecialFunc(:processSpecialKeys) glutMainLoop() func renderScene // Clear Color and Depth Buffers glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT) // Reset transformations glLoadIdentity() // Set the camera gluLookAt( 0.0, 0.0, 10.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0) glRotatef(angle, 0.0, 1.0, 0.0) glColor3f(red,green,blue); glBegin(GL_TRIANGLES) glVertex3f(-2.0,-2.0, 0.0) glVertex3f( 2.0, 0.0, 0.0) glVertex3f( 0.0, 2.0, 0.0) glEnd() angle+=0.1 glutSwapBuffers(); func changesize h = glutEventHeight() w = glutEventWidth() // Prevent a divide by zero, when window is too short // (you cant make a window of zero width). if (h = 0) h = 1 ok ratio = w * 1.0 / h // Use the Projection Matrix glMatrixMode(GL_PROJECTION) // Reset Matrix glLoadIdentity() // Set the viewport to be the entire window glViewport(0, 0, w, h) // Set the correct perspective. gluPerspective(45,ratio,1,100) // Get Back to the Modelview glMatrixMode(GL_MODELVIEW) func processNormalKeys key = GLUTEventKey() if key = 27 shutdown() ok func processSpecialKeys key = GLUTEventKey() switch key on GLUT_KEY_F1 red = 1.0 green = 0.0 blue = 0.0 on GLUT_KEY_F2 red = 0.0 green = 1.0 blue = 0.0 on GLUT_KEY_F3 red = 0.0 green = 0.0 blue = 1.0 off Screen Shot .. image:: freeglutshot5.png :alt: RingFreeGLUT .. index:: pair: Using RingOpenGL and RingFreeGLUT for 3D Graphics; The Camera The Camera ========== Example: .. code-block:: ring load "freeglut.ring" load "opengl21lib.ring" // angle of rotation for the camera direction angle=0.0 // actual vector representing the camera's direction lx=0.0 lz=-1.0 // XZ position of the camera x=0.0 z=5.0 func drawSnowMan glColor3f(1.0, 1.0, 1.0) // Draw Body glTranslatef(0.0 ,0.75, 0.0) glutSolidSphere(0.75,20,20) // Draw Head glTranslatef(0.0, 1.0, 0.0) glutSolidSphere(0.25,20,20) // Draw Eyes glPushMatrix() glColor3f(0.0,0.0,0.0) glTranslatef(0.05, 0.10, 0.18) glutSolidSphere(0.05,10,10) glTranslatef(-0.1, 0.0, 0.0) glutSolidSphere(0.05,10,10) glPopMatrix() // Draw Nose glColor3f(1.0, 0.5 , 0.5) glutSolidCone(0.08,0.5,10,2) func changeSize w = glutEventWidth() h = glutEventHeight() // Prevent a divide by zero, when window is too short // (you cant make a window of zero width). if h = 0 h = 1 ok ratio = w * 1.0 / h // Use the Projection Matrix glMatrixMode(GL_PROJECTION) // Reset Matrix glLoadIdentity() // Set the viewport to be the entire window glViewport(0, 0, w, h) // Set the correct perspective. gluPerspective(45.0, ratio, 0.1, 100.0); // Get Back to the Modelview glMatrixMode(GL_MODELVIEW) func processNormalKeys key = glutEventKey() if key = 27 shutdown() ok func renderScene // Clear Color and Depth Buffers glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT) // Reset transformations glLoadIdentity() // Set the camera gluLookAt( x, 1.0, z, x+lx, 1.0, z+lz, 0.0, 1.0, 0.0) // Draw ground glColor3f(0.9, 0.9, 0.9) glBegin(GL_QUADS) glVertex3f(-100.0, 0.0, -100.0) glVertex3f(-100.0, 0.0, 100.0) glVertex3f( 100.0, 0.0, 100.0) glVertex3f( 100.0, 0.0, -100.0) glEnd() // Draw 36 SnowMen for i = -3 to 2 for j=-3 to 2 glPushMatrix() glTranslatef(i*10.0,0,j * 10.0) drawSnowMan() glPopMatrix() next next glutSwapBuffers() func processSpecialKeys key = glutEventKey() fraction = 0.1 switch key on GLUT_KEY_LEFT angle -= 0.01 lx = sin(angle) lz = -cos(angle) on GLUT_KEY_RIGHT angle += 0.01 lx = sin(angle) lz = -cos(angle) on GLUT_KEY_UP x += lx * fraction z += lz * fraction on GLUT_KEY_DOWN x -= lx * fraction z -= lz * fraction off func main // init GLUT and create window glutInit() glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA) glutInitWindowPosition(100,100) glutInitWindowSize(320,320) glutCreateWindow("RingFreeGLUT - Test 7") // register callbacks glutDisplayFunc(:renderScene) glutReshapeFunc(:changeSize) glutIdleFunc(:renderScene) glutKeyboardFunc(:processNormalKeys) glutSpecialFunc(:processSpecialKeys) // OpenGL init glEnable(GL_DEPTH_TEST) // enter GLUT event processing cycle glutMainLoop() Screen Shot .. image:: freeglutshot6.png :alt: RingFreeGLUT Another Example: .. code-block:: ring load "freeglut.ring" load "opengl21lib.ring" // angle of rotation for the camera direction angle = 0.0 // actual vector representing the camera's direction lx=0.0 lz=-1.0 // XZ position of the camera x=0.0 z=5.0 // the key states. These variables will be zero //when no key is being presses deltaAngle = 0.0 deltaMove = 0 func changeSize w = glutEventWidth() h = glutEventHeight() // Prevent a divide by zero, when window is too short // (you cant make a window of zero width). if h = 0 h = 1 ok ratio = w * 1.0 / h // Use the Projection Matrix glMatrixMode(GL_PROJECTION) // Reset Matrix glLoadIdentity() // Set the viewport to be the entire window glViewport(0, 0, w, h) // Set the correct perspective. gluPerspective(45.0, ratio, 0.1, 100.0) // Get Back to the Modelview glMatrixMode(GL_MODELVIEW) func drawSnowMan glColor3f(1.0, 1.0, 1.0) // Draw Body glTranslatef(0.0 ,0.75, 0.0) glutSolidSphere(0.75,20,20) // Draw Head glTranslatef(0.0, 1.0, 0.0) glutSolidSphere(0.25,20,20) // Draw Eyes glPushMatrix() glColor3f(0.0,0.0,0.0) glTranslatef(0.05, 0.10, 0.18) glutSolidSphere(0.05,10,10) glTranslatef(-0.1, 0.0, 0.0) glutSolidSphere(0.05,10,10) glPopMatrix() // Draw Nose glColor3f(1.0, 0.5 , 0.5) glRotatef(0.0,1.0, 0.0, 0.0) glutSolidCone(0.08,0.5,10,2) func computePos deltaMove x += deltaMove * lx * 0.1 z += deltaMove * lz * 0.1 func computeDir deltaAngle angle += deltaAngle lx = sin(angle) lz = -cos(angle) func renderScene if deltaMove computePos(deltaMove) ok if deltaAngle computeDir(deltaAngle) ok // Clear Color and Depth Buffers glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT) // Reset transformations glLoadIdentity() // Set the camera gluLookAt( x, 1.0, z, x+lx, 1.0, z+lz, 0.0, 1.0, 0.0) // Draw ground glColor3f(0.9, 0.9, 0.9) glBegin(GL_QUADS) glVertex3f(-100.0, 0.0, -100.0) glVertex3f(-100.0, 0.0, 100.0) glVertex3f( 100.0, 0.0, 100.0) glVertex3f( 100.0, 0.0, -100.0) glEnd() // Draw 36 SnowMen for i = -3 to 2 for j=-3 to 2 glPushMatrix() glTranslatef(i*10.0,0,j * 10.0) drawSnowMan() glPopMatrix() next next glutSwapBuffers() func pressKey key = glutEventKey() xx = glutEventX() yy = glutEventY() switch key on GLUT_KEY_LEFT deltaAngle = -0.01 on GLUT_KEY_RIGHT deltaAngle = 0.01 on GLUT_KEY_UP deltaMove = 0.5 on GLUT_KEY_DOWN deltaMove = -0.5 off func releaseKey key = glutEventKey() switch key on GLUT_KEY_LEFT deltaAngle = 0.0 on GLUT_KEY_RIGHT deltaAngle = 0.0 on GLUT_KEY_UP deltaMove = 0 on GLUT_KEY_DOWN deltaMove = 0 off func main // init GLUT and create window glutInit() glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA) glutInitWindowPosition(100,100) glutInitWindowSize(320,320) glutCreateWindow("RingFreeGLUT - Test 8") // register callbacks glutDisplayFunc(:renderScene) glutReshapeFunc(:changeSize) glutIdleFunc(:renderScene) glutSpecialFunc(:pressKey) // here are the new entries glutIgnoreKeyRepeat(1) glutSpecialUpFunc(:releaseKey) // OpenGL init glEnable(GL_DEPTH_TEST) // enter GLUT event processing cycle glutMainLoop() .. index:: pair: Using RingOpenGL and RingFreeGLUT for 3D Graphics; Mouse Events Mouse Events ============ Example: .. code-block:: ring load "freeglut.ring" load "opengl21lib.ring" // angle of rotation for the camera direction angle = 0.0 // actual vector representing the camera's direction lx=0.0 lz=-1.0 // XZ position of the camera x=0.0 z=5.0 // the key states. These variables will be zero //when no key is being presses deltaAngle = 0.0 deltaMove = 0.0 xOrigin = -1 func changeSize w = glutEventWidth() h = glutEventHeight() // Prevent a divide by zero, when window is too short // (you cant make a window of zero width). if h = 0 h = 1 ok ratio = w * 1.0 / h // Use the Projection Matrix glMatrixMode(GL_PROJECTION) // Reset Matrix glLoadIdentity() // Set the viewport to be the entire window glViewport(0, 0, w, h) // Set the correct perspective. gluPerspective(45.0, ratio, 0.1, 100.0) // Get Back to the Modelview glMatrixMode(GL_MODELVIEW) func drawSnowMan glColor3f(1.0, 1.0, 1.0) // Draw Body glTranslatef(0.0 ,0.75, 0.0) glutSolidSphere(0.75,20,20) // Draw Head glTranslatef(0.0, 1.0, 0.0) glutSolidSphere(0.25,20,20) // Draw Eyes glPushMatrix() glColor3f(0.0,0.0,0.0) glTranslatef(0.05, 0.10, 0.18) glutSolidSphere(0.05,10,10) glTranslatef(-0.1, 0.0, 0.0) glutSolidSphere(0.05,10,10) glPopMatrix() // Draw Nose glColor3f(1.0, 0.5 , 0.5) glRotatef(0.0,1.0, 0.0, 0.0) glutSolidCone(0.08,0.5,10,2) func computePos deltaMove x += deltaMove * lx * 0.1 z += deltaMove * lz * 0.1 func renderScene if deltaMove computePos(deltaMove) ok // Clear Color and Depth Buffers glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT) // Reset transformations glLoadIdentity() // Set the camera gluLookAt( x, 1.0, z, x+lx, 1.0, z+lz, 0.0, 1.0, 0.0) // Draw ground glColor3f(0.9, 0.9, 0.9) glBegin(GL_QUADS) glVertex3f(-100.0, 0.0, -100.0) glVertex3f(-100.0, 0.0, 100.0) glVertex3f( 100.0, 0.0, 100.0) glVertex3f( 100.0, 0.0, -100.0) glEnd() // Draw 36 SnowMen for i = -3 to 2 for j=-3 to 2 glPushMatrix() glTranslatef(i*10.0,0,j * 10.0) drawSnowMan() glPopMatrix() next next glutSwapBuffers() func processNormalKeys key = glutEventKey() if key = 27 shutdown() ok func pressKey key = glutEventKey() switch key on GLUT_KEY_UP deltaMove = 0.5 on GLUT_KEY_DOWN deltaMove = -0.5 off func releaseKey key = glutEventKey() switch key on GLUT_KEY_UP deltaMove = 0 on GLUT_KEY_DOWN deltaMove = 0 off func mouseMove xx = glutEventX() yy = glutEventY() // this will only be true when the left button is down if xOrigin >= 0 // update deltaAngle deltaAngle = (xx - xOrigin) * 0.001 // update camera's direction lx = sin(angle + deltaAngle) lz = -cos(angle + deltaAngle) ok func mouseButton button = glutEventButton() state = glutEventState() xx = glutEventX() yy = glutEventY() // only start motion if the left button is pressed if button = GLUT_LEFT_BUTTON // when the button is released if state = GLUT_UP angle += deltaAngle xOrigin = -1 else // state = GLUT_DOWN xOrigin = xx ok fflush(stdout) ok func main // init GLUT and create window glutInit() glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA) glutInitWindowPosition(100,100) glutInitWindowSize(320,320) glutCreateWindow("RingFreeGLUT - Test 9") // register callbacks glutDisplayFunc(:renderScene) glutReshapeFunc(:changeSize) glutIdleFunc(:renderScene) glutIgnoreKeyRepeat(1) glutKeyboardFunc(:processNormalKeys) glutSpecialFunc(:pressKey) glutSpecialUpFunc(:releaseKey) // here are the two new functions glutMouseFunc(:mouseButton) glutMotionFunc(:mouseMove) // OpenGL init glEnable(GL_DEPTH_TEST) // enter GLUT event processing cycle glutMainLoop() .. index:: pair: Using RingOpenGL and RingFreeGLUT for 3D Graphics; Menu Events Menu Events =========== Example: .. code-block:: ring load "freeglut.ring" load "opengl21lib.ring" // angle of rotation for the camera direction angle = 0.0 // actual vector representing the camera's direction lx=0.0 lz=-1.0 // XZ position of the camera x=0.0 z=5.0 // the key states. These variables will be zero //when no key is being presses deltaAngle = 0.0 deltaMove = 0 xOrigin = -1 // Constant definitions for Menus // for RingFreeGLUT - We must have different ID for each menu item C_RED = 1 C_GREEN = 2 C_BLUE = 3 C_ORANGE = 4 C_FILL = 5 C_LINE = 6 C_SHRINK = 7 C_NORMAL = 8 // Pop up menu identifiers fillMenu= 0 shrinkMenu= 0 mainMenu=0 colorMenu=0 // color for the nose red = 1.0 blue=0.5 green=0.5 // scale of snowman scale = 1.0 // menu status menuFlag = 0 func changeSize w = glutEventWidth() h = glutEventHeight() // Prevent a divide by zero, when window is too short // (you cant make a window of zero width). if h = 0 h = 1 ok ratio = w * 1.0 / h // Use the Projection Matrix glMatrixMode(GL_PROJECTION) // Reset Matrix glLoadIdentity() // Set the viewport to be the entire window glViewport(0, 0, w, h) // Set the correct perspective. gluPerspective(45.0, ratio, 0.1, 100.0) // Get Back to the Modelview glMatrixMode(GL_MODELVIEW) func drawSnowMan glScalef(scale, scale, scale) glColor3f(1.0, 1.0, 1.0) // Draw Body glTranslatef(0.0 ,0.75, 0.0) glutSolidSphere(0.75,20,20) // Draw Head glTranslatef(0.0, 1.0, 0.0) glutSolidSphere(0.25,20,20) // Draw Eyes glPushMatrix() glColor3f(0.0,0.0,0.0) glTranslatef(0.05, 0.10, 0.18) glutSolidSphere(0.05,10,10) glTranslatef(-0.1, 0.0, 0.0) glutSolidSphere(0.05,10,10) glPopMatrix() // Draw Nose glColor3f(red, green, blue) glRotatef(0.0,1.0, 0.0, 0.0) glutSolidCone(0.08,0.5,10,2) glColor3f(1.0, 1.0, 1.0) func computePos deltaMove x += deltaMove * lx * 0.1 z += deltaMove * lz * 0.1 func renderScene if deltaMove computePos(deltaMove) ok // Clear Color and Depth Buffers glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT) // Reset transformations glLoadIdentity() // Set the camera gluLookAt( x, 1.0, z, x+lx, 1.0, z+lz, 0.0, 1.0, 0.0) // Draw ground glColor3f(0.9, 0.9, 0.9) glBegin(GL_QUADS) glVertex3f(-100.0, 0.0, -100.0) glVertex3f(-100.0, 0.0, 100.0) glVertex3f( 100.0, 0.0, 100.0) glVertex3f( 100.0, 0.0, -100.0) glEnd() // Draw 36 SnowMen for i = -3 to 2 for j = -3 to 2 glPushMatrix() glTranslatef(i*10.0, 0.0, j * 10.0) drawSnowMan() glPopMatrix() next next glutSwapBuffers() // ----------------------------------- // KEYBOARD // ----------------------------------- func processNormalKeys key = glutEventKey() xx = glutEventX() yy = glutEventY() glutSetMenu(mainMenu) switch key on 27 glutDestroyMenu(mainMenu) glutDestroyMenu(fillMenu) glutDestroyMenu(colorMenu) glutDestroyMenu(shrinkMenu) shutdown() on 's' if not menuFlag glutChangeToSubMenu(2,"Shrink",shrinkMenu) ok on 'c' if not menuFlag glutChangeToSubMenu(2,"Color",colorMenu) ok off if key = 27 shutdown() ok func pressKey key = glutEventKey() xx = glutEventX() yy = glutEventY() switch key on GLUT_KEY_UP deltaMove = 0.5 on GLUT_KEY_DOWN deltaMove = -0.5 off func releaseKey key = glutEventKey() switch key on GLUT_KEY_UP deltaMove = 0 on GLUT_KEY_DOWN deltaMove = 0 off // ----------------------------------- // MOUSE // ----------------------------------- func mouseMove xx = glutEventX() yy = glutEventY() // this will only be true when the left button is down if xOrigin >= 0 // update deltaAngle deltaAngle = (xx - xOrigin) * 0.001 // update camera's direction lx = sin(angle + deltaAngle) lz = -cos(angle + deltaAngle) ok func mouseButton button = glutEventButton() state = glutEventState() xx = glutEventX() yy = glutEventY() // only start motion if the left button is pressed if button = GLUT_LEFT_BUTTON // when the button is released if state = GLUT_UP angle += deltaAngle xOrigin = -1 else // state = GLUT_DOWN xOrigin = xx ok ok // ----------------------------------- // MENUS // ----------------------------------- func processMenuStatus status = glutEventStatus() xx = glutEventX() yy = glutEventY() if status = GLUT_MENU_IN_USE menuFlag = 1 else menuFlag = 0 ok func processMainMenu // nothing to do in here // all actions are for submenus func processFillMenu option = glutEventValue() switch option on C_FILL glPolygonMode(GL_FRONT, GL_FILL) on C_LINE glPolygonMode(GL_FRONT, GL_LINE) off func processShrinkMenu option = glutEventValue() switch option on C_SHRINK scale = 0.5 on C_NORMAL scale = 1.0 off func processColorMenu option = glutEventValue() switch option on C_RED red = 1.0 green = 0.0 blue = 0.0 on C_GREEN red = 0.0 green = 1.0 blue = 0.0 on C_BLUE red = 0.0 green = 0.0 blue = 1.0 on C_ORANGE red = 1.0 green = 0.5 blue = 0.5 off func createPopupMenus shrinkMenu = glutCreateMenu(:processShrinkMenu) glutAddMenuEntry("Shrink",C_SHRINK) glutAddMenuEntry("NORMAL",C_NORMAL) fillMenu = glutCreateMenu(:processFillMenu) glutAddMenuEntry("Fill",C_FILL) glutAddMenuEntry("Line",C_LINE) colorMenu = glutCreateMenu(:processColorMenu) glutAddMenuEntry("Red",C_RED) glutAddMenuEntry("Blue",C_BLUE) glutAddMenuEntry("Green",C_GREEN) glutAddMenuEntry("Orange",C_ORANGE) mainMenu = glutCreateMenu(:processMainMenu) glutAddSubMenu("Polygon Mode", fillMenu) glutAddSubMenu("Color", colorMenu) // attach the menu to the right button glutAttachMenu(GLUT_RIGHT_BUTTON) // this will allow us to know if the menu is active glutMenuStatusFunc(:processMenuStatus) // ----------------------------------- // MAIN // ----------------------------------- func main // init GLUT and create window glutInit() glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA) glutInitWindowPosition(100,100) glutInitWindowSize(320,320) glutCreateWindow("RingFreeGLUT - Test 10") // register callbacks glutDisplayFunc(:renderScene) glutReshapeFunc(:changeSize) glutIdleFunc(:renderScene) glutIgnoreKeyRepeat(1) glutKeyboardFunc(:processNormalKeys) glutSpecialFunc(:pressKey) glutSpecialUpFunc(:releaseKey) // here are the two new functions glutMouseFunc(:mouseButton) glutMotionFunc(:mouseMove) // OpenGL init glEnable(GL_DEPTH_TEST) glEnable(GL_CULL_FACE) // init Menus createPopupMenus() // enter GLUT event processing cycle glutMainLoop() Screen Shot .. image:: freeglutshot7.png :alt: RingFreeGLUT .. index:: pair: Using RingOpenGL and RingFreeGLUT for 3D Graphics; Using Fonts Using Fonts =========== Example: .. code-block:: ring load "freeglut.ring" load "opengl21lib.ring" // angle of rotation for the camera direction angle = 0.0 // actual vector representing the camera's direction lx=0.0 lz=-1.0 // XZ position of the camera x=0.0 z=5.0 // the key states. These variables will be zero //when no key is being presses deltaAngle = 0.0 deltaMove = 0 xOrigin = -1 // Constant definitions for Menus C_RED = 1 C_GREEN = 2 C_BLUE = 3 C_ORANGE = 4 C_FILL = 5 C_LINE = 6 // Pop up menu identifiers fillMenu=NULL fontMenu=NULL mainMenu=NULL colorMenu=NULL // color for the nose red = 1.0 blue=0.5 green=0.5 // scale of snowman scale = 1.0 // menu status menuFlag = 0 // default font font = GLUT_BITMAP_TIMES_ROMAN_24 C_INT_GLUT_BITMAP_8_BY_13 = 7 C_INT_GLUT_BITMAP_9_BY_15 = 8 C_INT_GLUT_BITMAP_TIMES_ROMAN_10 = 9 C_INT_GLUT_BITMAP_TIMES_ROMAN_24 = 10 C_INT_GLUT_BITMAP_HELVETICA_10 = 11 C_INT_GLUT_BITMAP_HELVETICA_12 = 12 C_INT_GLUT_BITMAP_HELVETICA_18 = 13 func changeSize w = glutEventWidth() h = glutEventHeight() // Prevent a divide by zero, when window is too short // (you cant make a window of zero width). if h = 0 h = 1 ok ratio = w * 1.0 / h // Use the Projection Matrix glMatrixMode(GL_PROJECTION) // Reset Matrix glLoadIdentity() // Set the viewport to be the entire window glViewport(0, 0, w, h) // Set the correct perspective. gluPerspective(45.0, ratio, 0.1, 100.0) // Get Back to the Modelview glMatrixMode(GL_MODELVIEW) func drawSnowMan glScalef(scale, scale, scale) glColor3f(1.0, 1.0, 1.0) // Draw Body glTranslatef(0.0 ,0.75, 0.0) glutSolidSphere(0.75,20,20) // Draw Head glTranslatef(0.0, 1.0, 0.0) glutSolidSphere(0.25,20,20) // Draw Eyes glPushMatrix() glColor3f(0.0,0.0,0.0) glTranslatef(0.05, 0.10, 0.18) glutSolidSphere(0.05,10,10) glTranslatef(-0.1, 0.0, 0.0) glutSolidSphere(0.05,10,10) glPopMatrix() // Draw Nose glColor3f(red, green, blue) glRotatef(0.0,1.0, 0.0, 0.0) glutSolidCone(0.08,0.5,10,2) glColor3f(1.0, 1.0, 1.0) func renderBitmapString x,y,z,font,string glRasterPos3f(x, y,z) for c in string glutBitmapCharacter(font,ascii(c)) next func computePos deltaMove x += deltaMove * lx * 0.1 z += deltaMove * lz * 0.1 func renderScene if deltaMove computePos(deltaMove) ok // Clear Color and Depth Buffers glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT) // Reset transformations glLoadIdentity() // Set the camera gluLookAt( x, 1.0, z, x+lx, 1.0, z+lz, 0.0, 1.0, 0.0) // Draw ground glColor3f(0.9, 0.9, 0.9) glBegin(GL_QUADS) glVertex3f(-100.0, 0.0, -100.0) glVertex3f(-100.0, 0.0, 100.0) glVertex3f( 100.0, 0.0, 100.0) glVertex3f( 100.0, 0.0, -100.0) glEnd() // Draw 36 SnowMen for i = -3 to 2 for j = -3 to 2 glPushMatrix() glTranslatef(i*10.0, 0.0, j * 10.0) drawSnowMan() number = (i+3)*6+(j+3) renderBitmapString(0.0, 0.5, 0.0,font ,""+number) glPopMatrix() next next glutSwapBuffers() // ----------------------------------- // KEYBOARD // ----------------------------------- func processNormalKeys key = glutEventKey() xx = glutEventX() yy = glutEventY() switch key on 27 glutDestroyMenu(mainMenu) glutDestroyMenu(fillMenu) glutDestroyMenu(colorMenu) glutDestroyMenu(fontMenu) Shutdown() off func pressKey key = glutEventKey() xx = glutEventX() yy = glutEventY() switch key on GLUT_KEY_UP deltaMove = 0.5 on GLUT_KEY_DOWN deltaMove = -0.5 off func releaseKey key = glutEventKey() switch key on GLUT_KEY_UP deltaMove = 0 on GLUT_KEY_DOWN deltaMove = 0 off // ----------------------------------- // MOUSE // ----------------------------------- func mouseMove xx = glutEventX() yy = glutEventY() // this will only be true when the left button is down if xOrigin >= 0 // update deltaAngle deltaAngle = (xx - xOrigin) * 0.001 // update camera's direction lx = sin(angle + deltaAngle) lz = -cos(angle + deltaAngle) ok func mouseButton button = glutEventButton() state = glutEventState() xx = glutEventX() yy = glutEventY() // only start motion if the left button is pressed if button = GLUT_LEFT_BUTTON // when the button is released if state = GLUT_UP angle += deltaAngle xOrigin = -1 else // state = GLUT_DOWN xOrigin = xx ok ok // ----------------------------------- // MENUS // ----------------------------------- func processMenuStatus status = glutEventStatus() if status = GLUT_MENU_IN_USE menuFlag = 1 else menuFlag = 0 ok func processMainMenu // nothing to do in here // all actions are for submenus func processFillMenu option = glutEventValue() switch option on C_FILL glPolygonMode(GL_FRONT, GL_FILL) on C_LINE glPolygonMode(GL_FRONT, GL_LINE) off func processFontMenu option = glutEventValue() switch (option) { on C_INT_GLUT_BITMAP_8_BY_13 font = GLUT_BITMAP_8_BY_13 on C_INT_GLUT_BITMAP_9_BY_15 font = GLUT_BITMAP_9_BY_15 on C_INT_GLUT_BITMAP_TIMES_ROMAN_10 font = GLUT_BITMAP_TIMES_ROMAN_10 on C_INT_GLUT_BITMAP_TIMES_ROMAN_24 font = GLUT_BITMAP_TIMES_ROMAN_24 on C_INT_GLUT_BITMAP_HELVETICA_10 font = GLUT_BITMAP_HELVETICA_10 on C_INT_GLUT_BITMAP_HELVETICA_12 font = GLUT_BITMAP_HELVETICA_12 on C_INT_GLUT_BITMAP_HELVETICA_18 font = GLUT_BITMAP_HELVETICA_18 off func processColorMenu option = glutEventValue() switch option on C_RED red = 1.0 green = 0.0 blue = 0.0 on C_GREEN red = 0.0 green = 1.0 blue = 0.0 on C_BLUE red = 0.0 green = 0.0 blue = 1.0 on C_ORANGE red = 1.0 green = 0.5 blue = 0.5 off func createPopupMenus fontMenu = glutCreateMenu(:processFontMenu) glutAddMenuEntry("BITMAP_8_BY_13 ",C_INT_GLUT_BITMAP_8_BY_13 ) glutAddMenuEntry("BITMAP_9_BY_15",C_INT_GLUT_BITMAP_9_BY_15 ) glutAddMenuEntry("BITMAP_TIMES_ROMAN_10 ",C_INT_GLUT_BITMAP_TIMES_ROMAN_10 ) glutAddMenuEntry("BITMAP_TIMES_ROMAN_24",C_INT_GLUT_BITMAP_TIMES_ROMAN_24 ) glutAddMenuEntry("BITMAP_HELVETICA_10 ",C_INT_GLUT_BITMAP_HELVETICA_10 ) glutAddMenuEntry("BITMAP_HELVETICA_12",C_INT_GLUT_BITMAP_HELVETICA_12 ) glutAddMenuEntry("BITMAP_HELVETICA_18",C_INT_GLUT_BITMAP_HELVETICA_18 ) fillMenu = glutCreateMenu(:processFillMenu) glutAddMenuEntry("Fill",C_FILL) glutAddMenuEntry("Line",C_LINE) colorMenu = glutCreateMenu(:processColorMenu) glutAddMenuEntry("Red",C_RED); glutAddMenuEntry("Blue",C_BLUE); glutAddMenuEntry("Green",C_GREEN); glutAddMenuEntry("Orange",C_ORANGE); mainMenu = glutCreateMenu(:processMainMenu) glutAddSubMenu("Polygon Mode", fillMenu) glutAddSubMenu("Color", colorMenu) glutAddSubMenu("Font",fontMenu) // attach the menu to the right button glutAttachMenu(GLUT_RIGHT_BUTTON) // this will allow us to know if the menu is active glutMenuStatusFunc(:processMenuStatus) // ----------------------------------- // MAIN // ----------------------------------- func main // init GLUT and create window glutInit() glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA) glutInitWindowPosition(100,100) glutInitWindowSize(320,320) glutCreateWindow("RingFreeGLUT - Test 11") // register callbacks glutDisplayFunc(:renderScene) glutReshapeFunc(:changeSize) glutIdleFunc(:renderScene) glutIgnoreKeyRepeat(1) glutKeyboardFunc(:processNormalKeys) glutSpecialFunc(:pressKey) glutSpecialUpFunc(:releaseKey) // here are the two new functions glutMouseFunc(:mouseButton) glutMotionFunc(:mouseMove) // OpenGL init glEnable(GL_DEPTH_TEST) glEnable(GL_CULL_FACE) // init Menus createPopupMenus() // enter GLUT event processing cycle glutMainLoop() Screen Shot .. image:: freeglutshot8.png :alt: RingFreeGLUT .. index:: pair: Using RingOpenGL and RingFreeGLUT for 3D Graphics; Frames Per Second Frames Per Second ================= Example .. code-block:: ring load "freeglut.ring" load "opengl21lib.ring" // angle of rotation for the camera direction angle = 0.0 // actual vector representing the camera's direction lx=0.0 lz=-1.0 // XZ position of the camera x=0.0 z=5.0 // the key states. These variables will be zero //when no key is being presses deltaAngle = 0.0 deltaMove = 0 xOrigin = -1 // Constant definitions for Menus C_RED = 1 C_GREEN = 2 C_BLUE = 3 C_ORANGE = 4 C_FILL = 5 C_LINE = 6 // Pop up menu identifiers fillMenu=NULL fontMenu=NULL mainMenu=NULL colorMenu=NULL // color for the nose red = 1.0 blue=0.5 green=0.5 // scale of snowman scale = 1.0 // menu status menuFlag = 0 // default font font = GLUT_BITMAP_TIMES_ROMAN_24 C_INT_GLUT_BITMAP_8_BY_13 = 7 C_INT_GLUT_BITMAP_9_BY_15 = 8 C_INT_GLUT_BITMAP_TIMES_ROMAN_10 = 9 C_INT_GLUT_BITMAP_TIMES_ROMAN_24 = 10 C_INT_GLUT_BITMAP_HELVETICA_10 = 11 C_INT_GLUT_BITMAP_HELVETICA_12 = 12 C_INT_GLUT_BITMAP_HELVETICA_18 = 13 // width and height of the window h = 0 w = 0 // variables to compute frames per second frame=0 time=0 timebase=0 s = "" func changeSize w = glutEventWidth() h = glutEventHeight() // Prevent a divide by zero, when window is too short // (you cant make a window of zero width). if h = 0 h = 1 ok ratio = w * 1.0 / h // Use the Projection Matrix glMatrixMode(GL_PROJECTION) // Reset Matrix glLoadIdentity() // Set the viewport to be the entire window glViewport(0, 0, w, h) // Set the correct perspective. gluPerspective(45.0, ratio, 0.1, 100.0) // Get Back to the Modelview glMatrixMode(GL_MODELVIEW) func drawSnowMan glScalef(scale, scale, scale) glColor3f(1.0, 1.0, 1.0) // Draw Body glTranslatef(0.0 ,0.75, 0.0) glutSolidSphere(0.75,20,20) // Draw Head glTranslatef(0.0, 1.0, 0.0) glutSolidSphere(0.25,20,20) // Draw Eyes glPushMatrix() glColor3f(0.0,0.0,0.0) glTranslatef(0.05, 0.10, 0.18) glutSolidSphere(0.05,10,10) glTranslatef(-0.1, 0.0, 0.0) glutSolidSphere(0.05,10,10) glPopMatrix() // Draw Nose glColor3f(red, green, blue) glRotatef(0.0,1.0, 0.0, 0.0) glutSolidCone(0.08,0.5,10,2) glColor3f(1.0, 1.0, 1.0) func renderBitmapString x,y,z,font,string glRasterPos3f(x, y,z) for c in string glutBitmapCharacter(font,ascii(c)) next func renderStrokeFontString x,y,z,font,string glPushMatrix() glTranslatef(x, y,z) glScalef(0.002, 0.002, 0.002) for c in string glutStrokeCharacter(font, Ascii(c)); next glPopMatrix() func restorePerspectiveProjection glMatrixMode(GL_PROJECTION) // restore previous projection matrix glPopMatrix() // get back to modelview mode glMatrixMode(GL_MODELVIEW) func setOrthographicProjection // switch to projection mode glMatrixMode(GL_PROJECTION) // save previous matrix which contains the //settings for the perspective projection glPushMatrix() // reset matrix glLoadIdentity() // set a 2D orthographic projection gluOrtho2D(0, w, h, 0) // switch back to modelview mode glMatrixMode(GL_MODELVIEW) func computePos deltaMove x += deltaMove * lx * 0.1 z += deltaMove * lz * 0.1 func renderScene if deltaMove computePos(deltaMove) ok // Clear Color and Depth Buffers glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT) // Reset transformations glLoadIdentity() // Set the camera gluLookAt( x, 1.0, z, x+lx, 1.0, z+lz, 0.0, 1.0, 0.0) // Draw ground glColor3f(0.9, 0.9, 0.9) glBegin(GL_QUADS) glVertex3f(-100.0, 0.0, -100.0) glVertex3f(-100.0, 0.0, 100.0) glVertex3f( 100.0, 0.0, 100.0) glVertex3f( 100.0, 0.0, -100.0) glEnd() // Draw 9 SnowMen for i = -3 to -1 for j = -3 to -1 glPushMatrix() glTranslatef(i*10.0, 0.0, j * 10.0) drawSnowMan() number = (i+3)*3+(j+3) renderBitmapString(0.0, 0.5, 0.0,font ,""+number) glPopMatrix() next next // Code to compute frames per second frame++ time=glutGet(GLUT_ELAPSED_TIME) if time - timebase > 1000 s = "RingFreeGLUT - FPS: " + (frame*1000.0/(time-timebase)) timebase = time frame = 0 ok // Code to display a string (fps) with bitmap fonts setOrthographicProjection() glPushMatrix() glLoadIdentity() renderBitmapString(5,30,0,GLUT_BITMAP_HELVETICA_18,s) glPopMatrix() restorePerspectiveProjection() glutSwapBuffers() // ----------------------------------- // KEYBOARD // ----------------------------------- func processNormalKeys key = glutEventKey() xx = glutEventX() yy = glutEventY() switch key on 27 glutDestroyMenu(mainMenu) glutDestroyMenu(fillMenu) glutDestroyMenu(colorMenu) glutDestroyMenu(fontMenu) Shutdown() off func pressKey key = glutEventKey() xx = glutEventX() yy = glutEventY() switch key on GLUT_KEY_UP deltaMove = 0.5 on GLUT_KEY_DOWN deltaMove = -0.5 off func releaseKey key = glutEventKey() switch key on GLUT_KEY_UP deltaMove = 0 on GLUT_KEY_DOWN deltaMove = 0 off // ----------------------------------- // MOUSE // ----------------------------------- func mouseMove xx = glutEventX() yy = glutEventY() // this will only be true when the left button is down if xOrigin >= 0 // update deltaAngle deltaAngle = (xx - xOrigin) * 0.001 // update camera's direction lx = sin(angle + deltaAngle) lz = -cos(angle + deltaAngle) ok func mouseButton button = glutEventButton() state = glutEventState() xx = glutEventX() yy = glutEventY() // only start motion if the left button is pressed if button = GLUT_LEFT_BUTTON // when the button is released if state = GLUT_UP angle += deltaAngle xOrigin = -1 else // state = GLUT_DOWN xOrigin = xx ok ok // ----------------------------------- // MENUS // ----------------------------------- func processMenuStatus status = glutEventStatus() if status = GLUT_MENU_IN_USE menuFlag = 1 else menuFlag = 0 ok func processMainMenu // nothing to do in here // all actions are for submenus func processFillMenu option = glutEventValue() switch option on C_FILL glPolygonMode(GL_FRONT, GL_FILL) on C_LINE glPolygonMode(GL_FRONT, GL_LINE) off func processFontMenu option = glutEventValue() switch (option) { on C_INT_GLUT_BITMAP_8_BY_13 font = GLUT_BITMAP_8_BY_13 on C_INT_GLUT_BITMAP_9_BY_15 font = GLUT_BITMAP_9_BY_15 on C_INT_GLUT_BITMAP_TIMES_ROMAN_10 font = GLUT_BITMAP_TIMES_ROMAN_10 on C_INT_GLUT_BITMAP_TIMES_ROMAN_24 font = GLUT_BITMAP_TIMES_ROMAN_24 on C_INT_GLUT_BITMAP_HELVETICA_10 font = GLUT_BITMAP_HELVETICA_10 on C_INT_GLUT_BITMAP_HELVETICA_12 font = GLUT_BITMAP_HELVETICA_12 on C_INT_GLUT_BITMAP_HELVETICA_18 font = GLUT_BITMAP_HELVETICA_18 off func processColorMenu option = glutEventValue() switch option on C_RED red = 1.0 green = 0.0 blue = 0.0 on C_GREEN red = 0.0 green = 1.0 blue = 0.0 on C_BLUE red = 0.0 green = 0.0 blue = 1.0 on C_ORANGE red = 1.0 green = 0.5 blue = 0.5 off func createPopupMenus fontMenu = glutCreateMenu(:processFontMenu) glutAddMenuEntry("BITMAP_8_BY_13 ",C_INT_GLUT_BITMAP_8_BY_13 ) glutAddMenuEntry("BITMAP_9_BY_15",C_INT_GLUT_BITMAP_9_BY_15 ) glutAddMenuEntry("BITMAP_TIMES_ROMAN_10 ",C_INT_GLUT_BITMAP_TIMES_ROMAN_10 ) glutAddMenuEntry("BITMAP_TIMES_ROMAN_24",C_INT_GLUT_BITMAP_TIMES_ROMAN_24 ) glutAddMenuEntry("BITMAP_HELVETICA_10 ",C_INT_GLUT_BITMAP_HELVETICA_10 ) glutAddMenuEntry("BITMAP_HELVETICA_12",C_INT_GLUT_BITMAP_HELVETICA_12 ) glutAddMenuEntry("BITMAP_HELVETICA_18",C_INT_GLUT_BITMAP_HELVETICA_18 ) fillMenu = glutCreateMenu(:processFillMenu) glutAddMenuEntry("Fill",C_FILL) glutAddMenuEntry("Line",C_LINE) colorMenu = glutCreateMenu(:processColorMenu) glutAddMenuEntry("Red",C_RED); glutAddMenuEntry("Blue",C_BLUE); glutAddMenuEntry("Green",C_GREEN); glutAddMenuEntry("Orange",C_ORANGE); mainMenu = glutCreateMenu(:processMainMenu) glutAddSubMenu("Polygon Mode", fillMenu) glutAddSubMenu("Color", colorMenu) glutAddSubMenu("Font",fontMenu) // attach the menu to the right button glutAttachMenu(GLUT_RIGHT_BUTTON) // this will allow us to know if the menu is active glutMenuStatusFunc(:processMenuStatus) // ----------------------------------- // MAIN // ----------------------------------- func main // init GLUT and create window glutInit() glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA) glutInitWindowPosition(100,100) glutInitWindowSize(320,320) glutCreateWindow("RingFreeGLUT - Test - 9 SnowMan") // register callbacks glutDisplayFunc(:renderScene) glutReshapeFunc(:changeSize) glutIdleFunc(:renderScene) glutIgnoreKeyRepeat(1) glutKeyboardFunc(:processNormalKeys) glutSpecialFunc(:pressKey) glutSpecialUpFunc(:releaseKey) // here are the two new functions glutMouseFunc(:mouseButton) glutMotionFunc(:mouseMove) // OpenGL init glEnable(GL_DEPTH_TEST) glEnable(GL_CULL_FACE) // init Menus createPopupMenus() // enter GLUT event processing cycle glutMainLoop() Screen Shots: The First screen shot .. image:: ring15freeglut.png :alt: RingFreeGLUT The Second screen shot .. image:: ring15freeglut2.png :alt: RingFreeGLUT .. index:: pair: Using RingOpenGL and RingFreeGLUT for 3D Graphics; Make a Cube using RingOpenGL and RingFreeGLUT Make a Cube using RingOpenGL and RingFreeGLUT ============================================= Example: .. code-block:: ring load "freeglut.ring" load "opengl21lib.ring" // ---------------------------------------------------------- // Global Variables // ---------------------------------------------------------- rotate_y=0 rotate_x=0 // ---------------------------------------------------------- // display() Callback function // ---------------------------------------------------------- func display // Clear screen and Z-buffer glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT) // Reset transformations glLoadIdentity() // Rotate when user changes rotate_x and rotate_y glRotatef( rotate_x, 1.0, 0.0, 0.0 ) glRotatef( rotate_y, 0.0, 1.0, 0.0 ) //Multi-colored side - FRONT glBegin(GL_POLYGON) glColor3f( 1.0, 0.0, 0.0 ) glVertex3f( 0.5, -0.5, -0.5 ) # P1 is red glColor3f( 0.0, 1.0, 0.0 ) glVertex3f( 0.5, 0.5, -0.5 ) # P2 is green glColor3f( 0.0, 0.0, 1.0 ) glVertex3f( -0.5, 0.5, -0.5 ) # P3 is blue glColor3f( 1.0, 0.0, 1.0 ) glVertex3f( -0.5, -0.5, -0.5 ) # P4 is purple glEnd() // White side - BACK glBegin(GL_POLYGON) glColor3f( 1.0, 1.0, 1.0 ) glVertex3f( 0.5, -0.5, 0.5 ) glVertex3f( 0.5, 0.5, 0.5 ) glVertex3f( -0.5, 0.5, 0.5 ) glVertex3f( -0.5, -0.5, 0.5 ) glEnd() // Purple side - RIGHT glBegin(GL_POLYGON) glColor3f( 1.0, 0.0, 1.0 ) glVertex3f( 0.5, -0.5, -0.5 ) glVertex3f( 0.5, 0.5, -0.5 ) glVertex3f( 0.5, 0.5, 0.5 ) glVertex3f( 0.5, -0.5, 0.5 ) glEnd() // Green side - LEFT glBegin(GL_POLYGON) glColor3f( 0.0, 1.0, 0.0 ) glVertex3f( -0.5, -0.5, 0.5 ) glVertex3f( -0.5, 0.5, 0.5 ) glVertex3f( -0.5, 0.5, -0.5 ) glVertex3f( -0.5, -0.5, -0.5 ) glEnd() // Blue side - TOP glBegin(GL_POLYGON) glColor3f( 0.0, 0.0, 1.0 ) glVertex3f( 0.5, 0.5, 0.5 ) glVertex3f( 0.5, 0.5, -0.5 ) glVertex3f( -0.5, 0.5, -0.5 ) glVertex3f( -0.5, 0.5, 0.5 ) glEnd() // Red side - BOTTOM glBegin(GL_POLYGON) glColor3f( 1.0, 0.0, 0.0 ) glVertex3f( 0.5, -0.5, -0.5 ) glVertex3f( 0.5, -0.5, 0.5 ) glVertex3f( -0.5, -0.5, 0.5 ) glVertex3f( -0.5, -0.5, -0.5 ) glEnd() glFlush() glutSwapBuffers() // ---------------------------------------------------------- // specialKeys() Callback Function // ---------------------------------------------------------- func specialKeys key = glutEventKey() // Right arrow - increase rotation by 5 degree switch Key on GLUT_KEY_RIGHT rotate_y += 5 // Left arrow - decrease rotation by 5 degree on GLUT_KEY_LEFT rotate_y -= 5 on GLUT_KEY_UP rotate_x += 5 on GLUT_KEY_DOWN rotate_x -= 5 off // Request display update glutPostRedisplay() // ---------------------------------------------------------- // main() function // ---------------------------------------------------------- func main // Initialize GLUT and process user parameters glutInit() // Request double buffered true color window with Z-buffer glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH) // Create window glutCreateWindow("Awesome Cube") // Enable Z-buffer depth test glEnable(GL_DEPTH_TEST) // Callback functions glutDisplayFunc(:display) glutSpecialFunc(:specialKeys) // Pass control to GLUT for events glutMainLoop() // Return to OS Screen Shot: .. image:: ring15opengl.png :alt: RingOpenGL