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    copied!<p>Looks like you're trying to construct a <a href="https://en.wikipedia.org/wiki/Surface_of_revolution" rel="nofollow noreferrer">surface of revolution</a>/<a href="https://en.wikipedia.org/wiki/Solid_of_revolution" rel="nofollow noreferrer">solid of revolution</a>/<a href="https://web.archive.org/web/20070808001022/http://www.delphi3d.net/articles/viewarticle.php?article=lathe.htm" rel="nofollow noreferrer">"lathe object"</a>.</p> <p>A working example:</p> <p><a href="https://i.stack.imgur.com/EGvGt.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/EGvGt.png" alt="lathe"></a> <br></p> <pre><code>#include &lt;GL/glut.h&gt; #include &lt;glm/glm.hpp&gt; #include &lt;vector&gt; #include &lt;cmath&gt; using namespace std; using namespace glm; struct Vertex { Vertex( const vec3&amp; position, const vec3&amp; normal ) : position( position ) , normal( normal ) {} vec3 position; vec3 normal; }; // spin the pts array around the Z axis. // pts.x will become the radius, and pts.y will become the height // pts should be sorted by y-coordinate vector&lt; Vertex &gt; Lathe( const vector&lt; vec2 &gt;&amp; pts, unsigned int segments = 32 ) { // precalculate circle points vector&lt; vec2 &gt; circlePts; for( unsigned int i = 0; i &lt;= segments; ++i ) { float angle = ( i / (float)segments ) * 3.14159f * 2.0f; circlePts.push_back( vec2( cos( angle ), sin( angle ) ) ); } // fill each layer typedef vector&lt; vec3 &gt; Layer; typedef vector&lt; Layer &gt; Layers; Layers layers( pts.size(), Layer( circlePts.size() ) ); for( size_t i = 0; i &lt; pts.size(); ++i ) { for( unsigned int j = 0; j &lt; circlePts.size(); ++j ) { layers[i][j] = vec3( circlePts[j] * pts[i].x, pts[i].y ); } } // move through layers generating triangles vector&lt; Vertex &gt; verts; for( size_t i = 1; i &lt; layers.size(); ++i ) { const Layer&amp; prvLayer = layers[ i-1 ]; const Layer&amp; curLayer = layers[ i-0 ]; for( size_t j = 1; j &lt; circlePts.size(); ++j ) { // upper = cur layer // UL -- UR // left | 0 / | right // = j-1 | / 1 | = j-0 // LL -- LR // lower = prv layer const vec3&amp; LL = prvLayer[ j-1 ]; // lower-left const vec3&amp; LR = prvLayer[ j-0 ]; // lower-right const vec3&amp; UL = curLayer[ j-1 ]; // upper-left const vec3&amp; UR = curLayer[ j-0 ]; // upper-right // triangle0: LL -&gt; UR -&gt; UL const vec3 normal0 = normalize( cross( UR - LL, UL - LL ) ); verts.push_back( Vertex( LL, normal0 ) ); verts.push_back( Vertex( UR, normal0 ) ); verts.push_back( Vertex( UL, normal0 ) ); // triangle1: LL -&gt; LR -&gt; UR const vec3 normal1 = normalize( cross( LR - LL, UL - LL ) ); verts.push_back( Vertex( LL, normal1 ) ); verts.push_back( Vertex( LR, normal1 ) ); verts.push_back( Vertex( UR, normal1 ) ); } } return verts; } // mouse state int btn; ivec2 startMouse; ivec2 startRot, curRot; void mouse(int button, int state, int x, int y ) { if( button == GLUT_LEFT_BUTTON &amp;&amp; state == GLUT_DOWN ) { btn = button; startMouse = ivec2( x, glutGet( GLUT_WINDOW_HEIGHT ) - y ); startRot = curRot; } } void motion( int x, int y ) { ivec2 curMouse( x, glutGet( GLUT_WINDOW_HEIGHT ) - y ); if( btn == GLUT_LEFT_BUTTON ) { curRot = startRot + ( curMouse - startMouse ); } glutPostRedisplay(); } vector&lt; Vertex &gt; model; void display() { glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT ); glMatrixMode( GL_PROJECTION ); glLoadIdentity(); double w = glutGet( GLUT_WINDOW_WIDTH ); double h = glutGet( GLUT_WINDOW_HEIGHT ); double ar = w / h; gluPerspective( 60, ar, 0.1, 40 ); glMatrixMode( GL_MODELVIEW ); glLoadIdentity(); glTranslatef( 0, 0, -10 ); glPushMatrix(); glRotatef( curRot.x % 360, 0, 1, 0 ); glRotatef( -curRot.y % 360, 1, 0, 0 ); // draw model if( !model.empty() ) { glColor3ub( 255, 0, 0 ); glEnableClientState( GL_VERTEX_ARRAY ); glEnableClientState( GL_NORMAL_ARRAY ); glVertexPointer( 3, GL_FLOAT, sizeof(Vertex), &amp;model[0].position ); glNormalPointer( GL_FLOAT, sizeof(Vertex), &amp;model[0].normal ); glDrawArrays( GL_TRIANGLES, 0, model.size() ); glDisableClientState( GL_VERTEX_ARRAY ); glDisableClientState( GL_NORMAL_ARRAY ); } // draw bounding cube glDisable( GL_LIGHTING ); glColor3ub( 255, 255, 255 ); glutWireCube( 7 ); glEnable( GL_LIGHTING ); glPopMatrix(); glutSwapBuffers(); } int main( int argc, char **argv ) { vector&lt; vec2 &gt; pts; pts.push_back( vec2( 0.1, -3 ) ); pts.push_back( vec2( 2, -2 ) ); pts.push_back( vec2( 3, -1 ) ); pts.push_back( vec2( 1, 0 ) ); pts.push_back( vec2( 3, 1 ) ); pts.push_back( vec2( 4, 2 ) ); pts.push_back( vec2( 4, 3 ) ); model = Lathe( pts ); glutInit( &amp;argc, argv ); glutInitDisplayMode( GLUT_RGBA | GLUT_DEPTH | GLUT_DOUBLE ); glutInitWindowSize( 640, 480 ); glutCreateWindow( "GLUT" ); glutDisplayFunc( display ); glutMouseFunc( mouse ); glutMotionFunc( motion ); glEnable( GL_DEPTH_TEST ); // set up lighting glShadeModel( GL_SMOOTH ); glEnable( GL_COLOR_MATERIAL ); glColorMaterial( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE ) ; glLightModeli( GL_LIGHT_MODEL_TWO_SIDE, GL_TRUE ); glEnable( GL_LIGHTING ); // set up "headlamp"-like light glEnable( GL_LIGHT0 ); glMatrixMode( GL_MODELVIEW ); glLoadIdentity(); GLfloat position[] = { 0, 0, 1, 0 }; glLightfv( GL_LIGHT0, GL_POSITION, position ); glPolygonMode( GL_FRONT, GL_FILL ); glPolygonMode( GL_BACK, GL_LINE ); glutMainLoop(); return 0; } </code></pre>
 

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