OpenGL: Difference between revisions
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'''Library:''' [[GLUT]] |
'''Library:''' [[GLUT]] |
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In this example, we use [http://en.wikipedia.org/wiki/OpenGL_Utility_Toolkit GLUT] to create a window and handle the main loop in a portable way. Windowing systems like MS Windows and X11 have their own platform-specific ways of handling these things. |
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Revision as of 20:07, 8 October 2007
OpenGL
You are encouraged to solve this task according to the task description, using any language you may know.
You are encouraged to solve this task according to the task description, using any language you may know.
In this task, the goal is to display a smooth shaded triangle with OpenGL.
C
Compiler: GCC 3.3.3
Library: GLUT
In this example, we use GLUT to create a window and handle the main loop in a portable way. Windowing systems like MS Windows and X11 have their own platform-specific ways of handling these things.
#include<GL/gl.h> #include<GL/glut.h> void paint(void) { glClearColor(0.3,0.3,0.3,0.0); glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT); glShadeModel(GL_SMOOTH); glLoadIdentity(); glTranslatef(-15.0, -15.0, 0.0); glBegin(GL_TRIANGLES); glColor3f(1.0, 0.0, 0.0); glVertex2f(0.0, 0.0); glColor3f(0.0, 1.0, 0.0); glVertex2f(30.0, 0.0); glColor3f(0.0, 0.0, 1.0); glVertex2f(0.0, 30.0); glEnd(); glFlush(); } void reshape(int width, int height) { glViewport(0, 0, width, height); glMatrixMode(GL_PROJECTION); glLoadIdentity(); glOrtho(-30.0, 30.0, -30.0, 30.0, -30.0, 30.0); glMatrixMode(GL_MODELVIEW); } int main(int argc, char *argv[]) { glutInit(&argc, argv); glutInitWindowSize(640, 480); glutCreateWindow("Triangle"); glutDisplayFunc(paint); glutReshapeFunc(reshape); glutMainLoop(); return 0; }
Haskell
import Graphics.Rendering.OpenGL import Graphics.UI.GLUT main = do getArgsAndInitialize createWindow "Triangle" displayCallback $= display matrixMode $= Projection loadIdentity ortho2D 0 30 0 30 matrixMode $= Modelview 0 mainLoop display = do clear [ColorBuffer] renderPrimitive Triangles $ do corner 1 0 0 5 5 corner 0 1 0 25 5 corner 0 0 1 5 25 swapBuffers corner r g b x y = do color (Color3 r g b :: Color3 GLfloat) vertex (Vertex2 x y :: Vertex2 GLfloat)
MAXScript
The choice of OpenGL or D3D in MAX is a user configuration setting. All MAXScript code is platform independent.
newMesh = mesh numVerts:3 numFaces:1 setMesh newMesh vertices:#([-100, -100, 0], [100, -100, 0], [-100, 100, 0]) faces:#([1, 2, 3]) defaultVCFaces newMesh setVertColor newMesh 1 red setVertColor newMesh 2 green setVertColor newMesh 3 blue setCVertMode newMesh true update newMesh viewport.setType #view_top max tool maximize viewport.SetRenderLevel #smoothhighlights
Perl
use OpenGL; sub triangle { glBegin GL_TRIANGLES; glColor3f 1.0, 0.0, 0.0; glVertex2f 5.0, 5.0; glColor3f 0.0, 1.0, 0.0; glVertex2f 25.0, 5.0; glColor3f 0.0, 0.0, 1.0; glVertex2f 5.0, 25.0; glEnd; }; glpOpenWindow; glMatrixMode GL_PROJECTION; glLoadIdentity; gluOrtho2D 0.0, 30.0, 0.0, 30.0; glMatrixMode GL_MODELVIEW; glClear GL_COLOR_BUFFER_BIT; triangle; glpFlush; glpMainLoop;