'' '' This Code Was Created By Jeff Molofee 2000 '' A HUGE Thanks To Fredric Echols For Cleaning Up '' And Optimizing The Base Code, Making It More Flexible! '' If You've Found This Code Useful, Please Let Me Know. '' Visit My Site At nehe.gamedev.net '' '' compile as: fbc -s gui lesson09.bas ''------------------------------------------------------------------------------ '' Use ESC key to quit '' T key to toggle Twinkling (on/off) '' PgUp key and PgDn key to Zoom in and out '' UpArrow, DnArrow to tilt screen up and down '' ''------------------------------------------------------------------------------ #include once "GL/gl.bi" #include once "GL/glu.bi" #include once "bmpload.bi" #include once "fbgfx.bi" ''for Scan code constants '' Setup our booleans const num = 50 '' Number Of Stars To Draw type STARS '' Create A Structure For Star r as integer '' Stars Color g as integer '' Stars Color b as integer '' Stars Color dist as single '' Stars Distance From Center angle as single '' Stars Current Angle end type declare function LoadGLTextures() as integer '' The texture loader and draw loop share these render controls. '' FB-LINTER: DISABLE-NEXT-LINE FBL301 dim shared texture(0) as GLuint '' Storage For One Texture dim shared twinkle as integer '' Twinkling Stars dim shared tp as integer '' T Pressed? dim star(0 to num-1) as STARS '' Need To Keep Track Of 'num' Stars dim zoom as single = -15.0 '' Distance Away From Stars dim tilt as single = 90.0 '' Tilt The View dim spin as single '' Spin Stars dim gl_loop as uinteger '' General loop Variable screen 18, 16, , 2 '' ReSizeGLScene glViewport 0, 0, 640, 480 '' Reset The Current Viewport glMatrixMode GL_PROJECTION '' Select The Projection Matrix glLoadIdentity '' Reset The Projection Matrix gluPerspective 45.0, 640.0/480.0, 0.1, 100.0 '' Calculate The Aspect Ratio Of The Window glMatrixMode GL_MODELVIEW '' Select The Modelview Matrix glLoadIdentity '' Reset The Modelview Matrix '' Jump To Texture Loading Routine if (not LoadGLTextures()) then end 1 '' If Texture Didn't Load Quit end if '' All Setup For OpenGL Goes Here glEnable GL_TEXTURE_2D '' Enable Texture Mapping glShadeModel GL_SMOOTH '' Enable Smooth Shading glClearColor 0.0, 0.0, 0.0, 0.5 '' Black Background glClearDepth 1.0 '' Depth Buffer Setup glHint GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST '' Really Nice Perspective Calculations glBlendFunc(GL_SRC_ALPHA, GL_ONE) '' Set The Blending Function For Translucency glEnable(GL_BLEND) randomize timer for gl_loop=0 to num -1 '' Create A Loop That Goes Through All The Stars star(gl_loop).angle = 0.0 '' Start All The Stars At Angle Zero star(gl_loop).dist = (gl_loop/num)*5.0 '' Calculate Distance From The Center star(gl_loop).r = int(rnd * 256) '' Give star(loop) A Random Red Intensity star(gl_loop).g = int(rnd * 256) '' Give star(loop) A Random Green Intensity star(gl_loop).b = int(rnd * 256) '' Give star(loop) A Random Blue Intensity next do glClear GL_COLOR_BUFFER_BIT or GL_DEPTH_BUFFER_BIT '' Clear The Screen And The Depth Buffer glBindTexture GL_TEXTURE_2D, texture(0) '' Select Our Texture for gl_loop=0 to num-1 '' loop Through All The Stars glLoadIdentity '' Reset The View Before We Draw Each Star glTranslatef 0.0, 0.0, zoom '' Zoom Into The Screen (Using The Value In 'zoom') glRotatef tilt, 1.0, 0.0, 0.0 '' Tilt The View (Using The Value In 'tilt') glRotatef star(gl_loop).angle, 0.0, 1.0, 0.0 '' Rotate To The Current Stars Angle glTranslatef star(gl_loop).dist, 0.0, 0.0 '' Move Forward On The X Plane glRotatef -star(gl_loop).angle, 0.0, 1.0, 0.0 '' Cancel The Current Stars Angle glRotatef -tilt, 1.0, 0.0, 0.0 '' Cancel The Screen Tilt if twinkle then '' Twinkling Stars Enabled '' Assign A Color Using Bytes glColor4ub star((num-gl_loop)-1).r, star((num-gl_loop)-1).g, star((num-gl_loop)-1).b, 255 glBegin GL_QUADS '' Begin Drawing The Textured Quad glTexCoord2f 0.0, 0.0 : glVertex3f -1.0, -1.0, 0.0 glTexCoord2f 1.0, 0.0 : glVertex3f 1.0, -1.0, 0.0 glTexCoord2f 1.0, 1.0 : glVertex3f 1.0, 1.0, 0.0 glTexCoord2f 0.0, 1.0 : glVertex3f -1.0, 1.0, 0.0 glEnd '' Done Drawing The Textured Quad end if glRotatef spin, 0.0, 0.0, 1.0 '' Rotate The Star On The Z Axis '' Assign A Color Using Bytes glColor4ub star(gl_loop).r, star(gl_loop).g, star(gl_loop).b, 255 glBegin GL_QUADS '' Begin Drawing The Textured Quad glTexCoord2f 0.0, 0.0 : glVertex3f -1.0, -1.0, 0.0 glTexCoord2f 1.0, 0.0 : glVertex3f 1.0, -1.0, 0.0 glTexCoord2f 1.0, 1.0 : glVertex3f 1.0, 1.0, 0.0 glTexCoord2f 0.0, 1.0 : glVertex3f -1.0, 1.0, 0.0 glEnd '' Done Drawing The Textured Quad spin = spin + 0.01 '' Used To Spin The Stars star(gl_loop).angle += gl_loop/num '' Changes The Angle Of A Star star(gl_loop).dist -= 0.01 '' Changes The Distance Of A Star if star(gl_loop).dist < 0.0 then '' Is The Star In The Middle Yet star(gl_loop).dist = star(gl_loop).dist + 5.0 '' Move The Star 5 Units From The Center star(gl_loop).r = int(rnd * 256) '' Give It A New Red Value star(gl_loop).g = int(rnd * 256) '' Give It A New Green Value star(gl_loop).b = int(rnd * 256) '' Give It A New Blue Value end if next '' Keyboard handlers if MULTIKEY(FB.SC_T) and not tp then '' T Key down tp = true twinkle = not twinkle '' toggle twinkle on /off end if if not (MULTIKEY(FB.SC_T)) then tp = false '' T key up if MULTIKEY(FB.SC_UP) then tilt = tilt - 0.5 '' If Up Arrow is Being Pressed, Tilt The Screen Up if MULTIKEY(FB.SC_DOWN) then tilt = tilt + 0.5 '' If Down Arrow Being Pressed, Tilt The Screen Down if MULTIKEY(FB.SC_PAGEUP) then zoom = zoom - 0.2f '' If Page Up is Being Pressed, Zoom Out if MULTIKEY(FB.SC_PAGEDOWN) then zoom = zoom + 0.2 '' If Page Down is Being Pressed, Zoom In flip '' flip or crash loop while MULTIKEY(FB.SC_ESCAPE) = 0 'Empty keyboard buffer while inkey <> "": wend end '' Load Bitmaps And Convert To Textures function LoadGLTextures() as integer dim Status as integer = false '' Status Indicator dim TextureImage(0) as BITMAP_RGBImageRec ptr '' Create Storage Space For The Texture ' Load The Bitmap, Check For Errors, If Bitmap's Not Found Quit TextureImage(0) = LoadBMP(exepath + "/data/Star.bmp") if TextureImage(0) then Status = true '' Set The Status To TRUE glGenTextures 1, @texture(0) '' Create The Texture ' Create Linear Filtered Texture glBindTexture GL_TEXTURE_2D, texture(0) glTexParameteri GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR glTexParameteri GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR glTexImage2D GL_TEXTURE_2D, 0, 3, TextureImage(0)->sizeX, TextureImage(0)->sizeY, 0, GL_RGB, GL_UNSIGNED_BYTE, TextureImage(0)->buffer end if if TextureImage(0) then '' If Texture Exists if TextureImage(0)->buffer then '' If Texture Image Exist deallocate(TextureImage(0)->buffer) '' Free The Texture Image Memory end if deallocate(TextureImage(0)) '' Free The Image Structure end if return Status '' Return The Status end function