quad.c

Mesa is an open-source implementation of the OpenGL specification - a system for rendering interacti

	break;
      case GLU_POINT:
	glBegin(GL_POINTS);
	for (i = 0; i < slices2; i++) {
	    sintemp = sinCache[i];
	    costemp = cosCache[i];
	    for (j = 0; j <= loops; j++) {
		radiusLow = outerRadius - deltaRadius * ((float) j / loops);

		if (qobj->textureCoords) {
		    texLow = radiusLow / outerRadius / 2;

		    glTexCoord2f(texLow * sinCache[i] + 0.5,
			    texLow * cosCache[i] + 0.5);
		}
		glVertex3f(radiusLow * sintemp, radiusLow * costemp, 0.0);
	    }
	}
	glEnd();
	break;
      case GLU_LINE:
	if (innerRadius == outerRadius) {
	    glBegin(GL_LINE_STRIP);

	    for (i = 0; i <= slices; i++) {
		if (qobj->textureCoords) {
		    glTexCoord2f(sinCache[i] / 2 + 0.5,
			    cosCache[i] / 2 + 0.5);
		}
		glVertex3f(innerRadius * sinCache[i],
			innerRadius * cosCache[i], 0.0);
	    }
	    glEnd();
	    break;
	}
	for (j = 0; j <= loops; j++) {
	    radiusLow = outerRadius - deltaRadius * ((float) j / loops);
	    if (qobj->textureCoords) {
		texLow = radiusLow / outerRadius / 2;
	    }

	    glBegin(GL_LINE_STRIP);
	    for (i = 0; i <= slices; i++) {
		if (qobj->textureCoords) {
		    glTexCoord2f(texLow * sinCache[i] + 0.5,
			    texLow * cosCache[i] + 0.5);
		}
		glVertex3f(radiusLow * sinCache[i],
			radiusLow * cosCache[i], 0.0);
	    }
	    glEnd();
	}
	for (i=0; i < slices2; i++) {
	    sintemp = sinCache[i];
	    costemp = cosCache[i];
	    glBegin(GL_LINE_STRIP);
	    for (j = 0; j <= loops; j++) {
		radiusLow = outerRadius - deltaRadius * ((float) j / loops);
		if (qobj->textureCoords) {
		    texLow = radiusLow / outerRadius / 2;
		}

		if (qobj->textureCoords) {
		    glTexCoord2f(texLow * sinCache[i] + 0.5,
			    texLow * cosCache[i] + 0.5);
		}
		glVertex3f(radiusLow * sintemp, radiusLow * costemp, 0.0);
	    }
	    glEnd();
	}
	break;
      case GLU_SILHOUETTE:
	if (sweepAngle < 360.0) {
	    for (i = 0; i <= slices; i+= slices) {
		sintemp = sinCache[i];
		costemp = cosCache[i];
		glBegin(GL_LINE_STRIP);
		for (j = 0; j <= loops; j++) {
		    radiusLow = outerRadius - deltaRadius * ((float) j / loops);

		    if (qobj->textureCoords) {
			texLow = radiusLow / outerRadius / 2;
			glTexCoord2f(texLow * sinCache[i] + 0.5,
				texLow * cosCache[i] + 0.5);
		    }
		    glVertex3f(radiusLow * sintemp, radiusLow * costemp, 0.0);
		}
		glEnd();
	    }
	}
	for (j = 0; j <= loops; j += loops) {
	    radiusLow = outerRadius - deltaRadius * ((float) j / loops);
	    if (qobj->textureCoords) {
		texLow = radiusLow / outerRadius / 2;
	    }

	    glBegin(GL_LINE_STRIP);
	    for (i = 0; i <= slices; i++) {
		if (qobj->textureCoords) {
		    glTexCoord2f(texLow * sinCache[i] + 0.5,
			    texLow * cosCache[i] + 0.5);
		}
		glVertex3f(radiusLow * sinCache[i],
			radiusLow * cosCache[i], 0.0);
	    }
	    glEnd();
	    if (innerRadius == outerRadius) break;
	}
	break;
      default:
	break;
    }
}

void GLAPIENTRY
gluSphere(GLUquadric *qobj, GLdouble radius, GLint slices, GLint stacks)
{
    GLint i,j;
    GLfloat sinCache1a[CACHE_SIZE];
    GLfloat cosCache1a[CACHE_SIZE];
    GLfloat sinCache2a[CACHE_SIZE];
    GLfloat cosCache2a[CACHE_SIZE];
    GLfloat sinCache3a[CACHE_SIZE];
    GLfloat cosCache3a[CACHE_SIZE];
    GLfloat sinCache1b[CACHE_SIZE];
    GLfloat cosCache1b[CACHE_SIZE];
    GLfloat sinCache2b[CACHE_SIZE];
    GLfloat cosCache2b[CACHE_SIZE];
    GLfloat sinCache3b[CACHE_SIZE];
    GLfloat cosCache3b[CACHE_SIZE];
    GLfloat angle;
    GLfloat zLow, zHigh;
    GLfloat sintemp1 = 0.0, sintemp2 = 0.0, sintemp3 = 0.0, sintemp4 = 0.0;
    GLfloat costemp1 = 0.0, costemp2 = 0.0, costemp3 = 0.0, costemp4 = 0.0;
    GLboolean needCache2, needCache3;
    GLint start, finish;

    if (slices >= CACHE_SIZE) slices = CACHE_SIZE-1;
    if (stacks >= CACHE_SIZE) stacks = CACHE_SIZE-1;
    if (slices < 2 || stacks < 1 || radius < 0.0) {
	gluQuadricError(qobj, GLU_INVALID_VALUE);
	return;
    }

    /* Cache is the vertex locations cache */
    /* Cache2 is the various normals at the vertices themselves */
    /* Cache3 is the various normals for the faces */
    needCache2 = needCache3 = GL_FALSE;

    if (qobj->normals == GLU_SMOOTH) {
	needCache2 = GL_TRUE;
    }

    if (qobj->normals == GLU_FLAT) {
	if (qobj->drawStyle != GLU_POINT) {
	    needCache3 = GL_TRUE;
	}
	if (qobj->drawStyle == GLU_LINE) {
	    needCache2 = GL_TRUE;
	}
    }

    for (i = 0; i < slices; i++) {
	angle = 2 * PI * i / slices;
	sinCache1a[i] = SIN(angle);
	cosCache1a[i] = COS(angle);
	if (needCache2) {
	    sinCache2a[i] = sinCache1a[i];
	    cosCache2a[i] = cosCache1a[i];
	}
    }

    for (j = 0; j <= stacks; j++) {
	angle = PI * j / stacks;
	if (needCache2) {
	    if (qobj->orientation == GLU_OUTSIDE) {
		sinCache2b[j] = SIN(angle);
		cosCache2b[j] = COS(angle);
	    } else {
		sinCache2b[j] = -SIN(angle);
		cosCache2b[j] = -COS(angle);
	    }
	}
	sinCache1b[j] = radius * SIN(angle);
	cosCache1b[j] = radius * COS(angle);
    }
    /* Make sure it comes to a point */
    sinCache1b[0] = 0;
    sinCache1b[stacks] = 0;

    if (needCache3) {
	for (i = 0; i < slices; i++) {
	    angle = 2 * PI * (i-0.5) / slices;
	    sinCache3a[i] = SIN(angle);
	    cosCache3a[i] = COS(angle);
	}
	for (j = 0; j <= stacks; j++) {
	    angle = PI * (j - 0.5) / stacks;
	    if (qobj->orientation == GLU_OUTSIDE) {
		sinCache3b[j] = SIN(angle);
		cosCache3b[j] = COS(angle);
	    } else {
		sinCache3b[j] = -SIN(angle);
		cosCache3b[j] = -COS(angle);
	    }
	}
    }

    sinCache1a[slices] = sinCache1a[0];
    cosCache1a[slices] = cosCache1a[0];
    if (needCache2) {
	sinCache2a[slices] = sinCache2a[0];
	cosCache2a[slices] = cosCache2a[0];
    }
    if (needCache3) {
	sinCache3a[slices] = sinCache3a[0];
	cosCache3a[slices] = cosCache3a[0];
    }

    switch (qobj->drawStyle) {
      case GLU_FILL:
	/* Do ends of sphere as TRIANGLE_FAN's (if not texturing)
	** We don't do it when texturing because we need to respecify the
	** texture coordinates of the apex for every adjacent vertex (because
	** it isn't a constant for that point)
	*/
	if (!(qobj->textureCoords)) {
	    start = 1;
	    finish = stacks - 1;

	    /* Low end first (j == 0 iteration) */
	    sintemp2 = sinCache1b[1];
	    zHigh = cosCache1b[1];
	    switch(qobj->normals) {
	      case GLU_FLAT:
		sintemp3 = sinCache3b[1];
		costemp3 = cosCache3b[1];
		break;
	      case GLU_SMOOTH:
		sintemp3 = sinCache2b[1];
		costemp3 = cosCache2b[1];
		glNormal3f(sinCache2a[0] * sinCache2b[0],
			cosCache2a[0] * sinCache2b[0],
			cosCache2b[0]);
		break;
	      default:
		break;
	    }
	    glBegin(GL_TRIANGLE_FAN);
	    glVertex3f(0.0, 0.0, radius);
	    if (qobj->orientation == GLU_OUTSIDE) {
		for (i = slices; i >= 0; i--) {
		    switch(qobj->normals) {
		      case GLU_SMOOTH:
			glNormal3f(sinCache2a[i] * sintemp3,
				cosCache2a[i] * sintemp3,
				costemp3);
			break;
		      case GLU_FLAT:
			if (i != slices) {
			    glNormal3f(sinCache3a[i+1] * sintemp3,
				    cosCache3a[i+1] * sintemp3,
				    costemp3);
			}
			break;
		      case GLU_NONE:
		      default:
			break;
		    }
		    glVertex3f(sintemp2 * sinCache1a[i],
			    sintemp2 * cosCache1a[i], zHigh);
		}
	    } else {
		for (i = 0; i <= slices; i++) {
		    switch(qobj->normals) {
		      case GLU_SMOOTH:
			glNormal3f(sinCache2a[i] * sintemp3,
				cosCache2a[i] * sintemp3,
				costemp3);
			break;
		      case GLU_FLAT:
			glNormal3f(sinCache3a[i] * sintemp3,
				cosCache3a[i] * sintemp3,
				costemp3);
			break;
		      case GLU_NONE:
		      default:
			break;
		    }
		    glVertex3f(sintemp2 * sinCache1a[i],
			    sintemp2 * cosCache1a[i], zHigh);
		}
	    }
	    glEnd();

	    /* High end next (j == stacks-1 iteration) */
	    sintemp2 = sinCache1b[stacks-1];
	    zHigh = cosCache1b[stacks-1];
	    switch(qobj->normals) {
	      case GLU_FLAT:
		sintemp3 = sinCache3b[stacks];
		costemp3 = cosCache3b[stacks];
		break;
	      case GLU_SMOOTH:
		sintemp3 = sinCache2b[stacks-1];
		costemp3 = cosCache2b[stacks-1];
		glNormal3f(sinCache2a[stacks] * sinCache2b[stacks],
			cosCache2a[stacks] * sinCache2b[stacks],
			cosCache2b[stacks]);
		break;
	      default:
		break;
	    }
	    glBegin(GL_TRIANGLE_FAN);
	    glVertex3f(0.0, 0.0, -radius);
	    if (qobj->orientation == GLU_OUTSIDE) {
		for (i = 0; i <= slices; i++) {
		    switch(qobj->normals) {
		      case GLU_SMOOTH:
			glNormal3f(sinCache2a[i] * sintemp3,
				cosCache2a[i] * sintemp3,
				costemp3);
			break;
		      case GLU_FLAT:
			glNormal3f(sinCache3a[i] * sintemp3,
				cosCache3a[i] * sintemp3,
				costemp3);
			break;
		      case GLU_NONE:
		      default:
			break;
		    }
		    glVertex3f(sintemp2 * sinCache1a[i],
			    sintemp2 * cosCache1a[i], zHigh);
		}
	    } else {
		for (i = slices; i >= 0; i--) {
		    switch(qobj->normals) {
		      case GLU_SMOOTH:
			glNormal3f(sinCache2a[i] * sintemp3,
				cosCache2a[i] * sintemp3,
				costemp3);
			break;
		      case GLU_FLAT:
			if (i != slices) {
			    glNormal3f(sinCache3a[i+1] * sintemp3,
				    cosCache3a[i+1] * sintemp3,
				    costemp3);
			}
			break;
		      case GLU_NONE:
		      default:
			break;
		    }
		    glVertex3f(sintemp2 * sinCache1a[i],
			    sintemp2 * cosCache1a[i], zHigh);
		}
	    }
	    glEnd();
	} else {
	    start = 0;
	    finish = stacks;
	}
	for (j = start; j < finish; j++) {
	    zLow = cosCache1b[j];
	    zHigh = cosCache1b[j+1];
	    sintemp1 = sinCache1b[j];
	    sintemp2 = sinCache1b[j+1];
	    switch(qobj->normals) {
	      case GLU_FLAT:
		sintemp4 = sinCache3b[j+1];
		costemp4 = cosCache3b[j+1];
		break;
	      case GLU_SMOOTH:
		if (qobj->orientation == GLU_OUTSIDE) {
		    sintemp3 = sinCache2b[j+1];
		    costemp3 = cosCache2b[j+1];
		    sintemp4 = sinCache2b[j];
		    costemp4 = cosCache2b[j];
		} else {
		    sintemp3 = sinCache2b[j];
		    costemp3 = cosCache2b[j];
		    sintemp4 = sinCache2b[j+1];
		    costemp4 = cosCache2b[j+1];
		}
		break;
	      default:
		break;
	    }

	    glBegin(GL_QUAD_STRIP);
	    for (i = 0; i <= slices; i++) {
		switch(qobj->normals) {
		  case GLU_SMOOTH:
		    glNormal3f(sinCache2a[i] * sintemp3,
			    cosCache2a[i] * sintemp3,
			    costemp3);
		    break;
		  case GLU_FLAT:
		  case GLU_NONE:
		  default:
		    break;
		}
		if (qobj->orientation == GLU_OUTSIDE) {
		    if (qobj->textureCoords) {
			glTexCoord2f(1 - (float) i / slices,
				1 - (float) (j+1) / stacks);
		    }
		    glVertex3f(sintemp2 * sinCache1a[i],
			    sintemp2 * cosCache1a[i], zHigh);
		} else {
		    if (qobj->textureCoords) {
			glTexCoord2f(1 - (float) i / slices,
				1 - (float) j / stacks);
		    }
		    glVertex3f(sintemp1 * sinCache1a[i],
			    sintemp1 * cosCache1a[i], zLow);
		}
		switch(qobj->normals) {
		  case GLU_SMOOTH:
		    glNormal3f(sinCache2a[i] * sintemp4,
			    cosCache2a[i] * sintemp4,
			    costemp4);
		    break;
		  case GLU_FLAT:
		    glNormal3f(sinCache3a[i] * sintemp4,
			    cosCache3a[i] * sintemp4,
			    costemp4);
		    break;
		  case GLU_NONE:
		  default:
		    break;
		}
		if (qobj->orientation == GLU_OUTSIDE) {
		    if (qobj->textureCoords) {
			glTexCoord2f(1 - (float) i / slices,
				1 - (float) j / stacks);
		    }
		    glVertex3f(sintemp1 * sinCache1a[i],
			    sintemp1 * cosCache1a[i], zLow);
		} else {
		    if (qobj->textureCoords) {
			glTexCoord2f(1 - (float) i / slices,
				1 - (float) (j+1) / stacks);
		    }
		    glVertex3f(sintemp2 * sinCache1a[i],
			    sintemp2 * cosCache1a[i], zHigh);
		}
	    }
	    glEnd();
	}
	break;
      case GLU_POINT:
	glBegin(GL_POINTS);
	for (j = 0; j <= stacks; j++) {
	    sintemp1 = sinCache1b[j];
	    costemp1 = cosCache1b[j];
	    switch(qobj->normals) {
	      case GLU_FLAT:
	      case GLU_SMOOTH:
		sintemp2 = sinCache2b[j];
		costemp2 = cosCache2b[j];
		break;
	      default:
		break;
	    }
	    for (i = 0; i < slices; i++) {
		switch(qobj->normals) {
		  case GLU_FLAT:
		  case GLU_SMOOTH:
		    glNormal3f(sinCache2a[i] * sintemp2,
			    cosCache2a[i] * sintemp2,
			    costemp2);
		    break;
		  case GLU_NONE:
		  default:
		    break;
		}

		zLow = j * radius / stacks;

		if (qobj->textureCoords) {
		    glTexCoord2f(1 - (float) i / slices,
			    1 - (float) j / stacks);
		}
		glVertex3f(sintemp1 * sinCache1a[i],
			sintemp1 * cosCache1a[i], costemp1);
	    }
	}
	glEnd();
	break;
      case GLU_LINE:
      case GLU_SILHOUETTE:
	for (j = 1; j < stacks; j++) {
	    sintemp1 = sinCache1b[j];
	    costemp1 = cosCache1b[j];
	    switch(qobj->normals) {
	      case GLU_FLAT:
	      case GLU_SMOOTH:
		sintemp2 = sinCache2b[j];
		costemp2 = cosCache2b[j];
		break;
	      default:
		break;
	    }

	    glBegin(GL_LINE_STRIP);
	    for (i = 0; i <= slices; i++) {
		switch(qobj->normals) {
		  case GLU_FLAT:
		    glNormal3f(sinCache3a[i] * sintemp2,
			    cosCache3a[i] * sintemp2,
			    costemp2);
		    break;
		  case GLU_SMOOTH:
		    glNormal3f(sinCache2a[i] * sintemp2,
			    cosCache2a[i] * sintemp2,
			    costemp2);
		    break;
		  case GLU_NONE:
		  default:
		    break;
		}
		if (qobj->textureCoords) {
		    glTexCoord2f(1 - (float) i / slices,
			    1 - (float) j / stacks);
		}
		glVertex3f(sintemp1 * sinCache1a[i],
			sintemp1 * cosCache1a[i], costemp1);
	    }
	    glEnd();
	}
	for (i = 0; i < slices; i++) {
	    sintemp1 = sinCache1a[i];
	    costemp1 = cosCache1a[i];
	    switch(qobj->normals) {
	      case GLU_FLAT:
	      case GLU_SMOOTH:
		sintemp2 = sinCache2a[i];
		costemp2 = cosCache2a[i];
		break;
	      default:
		break;
	    }

	    glBegin(GL_LINE_STRIP);
	    for (j = 0; j <= stacks; j++) {
		switch(qobj->normals) {
		  case GLU_FLAT:
		    glNormal3f(sintemp2 * sinCache3b[j],
			    costemp2 * sinCache3b[j],
			    cosCache3b[j]);
		    break;
		  case GLU_SMOOTH:
		    glNormal3f(sintemp2 * sinCache2b[j],
			    costemp2 * sinCache2b[j],
			    cosCache2b[j]);
		    break;
		  case GLU_NONE:
		  default:
		    break;
		}

		if (qobj->textureCoords) {
		    glTexCoord2f(1 - (float) i / slices,
			    1 - (float) j / stacks);
		}
		glVertex3f(sintemp1 * sinCache1b[j],
			costemp1 * sinCache1b[j], cosCache1b[j]);
	    }
	    glEnd();
	}
	break;
      default:
	break;
    }
}