Wie bewirbt man Textur glutSolidCube

Question

kann ich tutorials über Mapping-Texturen zu Polygonen finden Eckpunkten usw. aber nichts Angabe darüber, wie eine Textur auf einem Würfel (oder anderes Material) mit Schwemme (glutSolidCube) gezogen anzuwenden.

Ich tue so etwas wie:

glTexEnvfv(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, decal);
glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, repeat);
glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, repeat);
glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, nearest);
glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, nearest);

glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
glTexImage2D(GL_TEXTURE_2D, 0, 4, myImageWidth, myImageHeight, 0, GL_RGBA, GL_UNSIGNED_BYTE, (GLvoid *)myImage);

//...

glEnable(GL_TEXTURE_2D);

//now draw the cube
glutSolidCube(N);

Dadurch erhalte ich die Textur auf den Würfel gelten, sondern der ganze Würfel bekommt die Farbe des ersten Bytes in der Textur!

Gibt es eine Möglichkeit, eine Textur an einen festen Würfel abzubilden (und andere Feststoffe) bei der Verwendung von glutSolidCube?

Answer 1

Nein, da glutSolidCube() nicht Texturkoordinaten erzeugt. Glücklicherweise aber ist glutSolidCube() einfach, sich selbst zu implementieren und Texturkoordinaten hinzuzufügen. Hier ist der Quellcode glutSolidCube() und die damit verbundenen Funktionen, von http://www.opengl.org/resources/libraries/glut/ :

/* Copyright (c) Mark J. Kilgard, 1994, 1997. */

/**                                                                             
(c) Copyright 1993, Silicon Graphics, Inc.                                      

ALL RIGHTS RESERVED                                                             

Permission to use, copy, modify, and distribute this software                   
for any purpose and without fee is hereby granted, provided                     
that the above copyright notice appear in all copies and that                   
both the copyright notice and this permission notice appear in                  
supporting documentation, and that the name of Silicon                          
Graphics, Inc. not be used in advertising or publicity                          
pertaining to distribution of the software without specific,                    
written prior permission.

THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU
"AS-IS" AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR
OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.  IN NO
EVENT SHALL SILICON GRAPHICS, INC.  BE LIABLE TO YOU OR ANYONE
ELSE FOR ANY DIRECT, SPECIAL, INCIDENTAL, INDIRECT OR
CONSEQUENTIAL DAMAGES OF ANY KIND, OR ANY DAMAGES WHATSOEVER,
INCLUDING WITHOUT LIMITATION, LOSS OF PROFIT, LOSS OF USE,
SAVINGS OR REVENUE, OR THE CLAIMS OF THIRD PARTIES, WHETHER OR
NOT SILICON GRAPHICS, INC.  HAS BEEN ADVISED OF THE POSSIBILITY
OF SUCH LOSS, HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
ARISING OUT OF OR IN CONNECTION WITH THE POSSESSION, USE OR
PERFORMANCE OF THIS SOFTWARE.

US Government Users Restricted Rights

Use, duplication, or disclosure by the Government is subject to
restrictions set forth in FAR 52.227.19(c)(2) or subparagraph
(c)(1)(ii) of the Rights in Technical Data and Computer
Software clause at DFARS 252.227-7013 and/or in similar or
successor clauses in the FAR or the DOD or NASA FAR
Supplement.  Unpublished-- rights reserved under the copyright
laws of the United States.  Contractor/manufacturer is Silicon
Graphics, Inc., 2011 N.  Shoreline Blvd., Mountain View, CA
94039-7311.

OpenGL(TM) is a trademark of Silicon Graphics, Inc.
*/

static void
drawBox(GLfloat size, GLenum type)
{
  static GLfloat n[6][3] =
  {
    {-1.0, 0.0, 0.0},
    {0.0, 1.0, 0.0},
    {1.0, 0.0, 0.0},
    {0.0, -1.0, 0.0},
    {0.0, 0.0, 1.0},
    {0.0, 0.0, -1.0}
  };
  static GLint faces[6][4] =
  {
    {0, 1, 2, 3},
    {3, 2, 6, 7},
    {7, 6, 5, 4},
    {4, 5, 1, 0},
    {5, 6, 2, 1},
    {7, 4, 0, 3}
  };
  GLfloat v[8][3];
  GLint i;

  v[0][0] = v[1][0] = v[2][0] = v[3][0] = -size / 2;
  v[4][0] = v[5][0] = v[6][0] = v[7][0] = size / 2;
  v[0][1] = v[1][1] = v[4][1] = v[5][1] = -size / 2;
  v[2][1] = v[3][1] = v[6][1] = v[7][1] = size / 2;
  v[0][2] = v[3][2] = v[4][2] = v[7][2] = -size / 2;
  v[1][2] = v[2][2] = v[5][2] = v[6][2] = size / 2;

  for (i = 5; i >= 0; i--) {
    glBegin(type);
    glNormal3fv(&n[i][0]);
    glVertex3fv(&v[faces[i][0]][0]);
    glVertex3fv(&v[faces[i][1]][0]);
    glVertex3fv(&v[faces[i][2]][0]);
    glVertex3fv(&v[faces[i][3]][0]);
    glEnd();
  }
}

void APIENTRY
glutSolidCube(GLdouble size)
{
  drawBox(size, GL_QUADS);
}

Fügen Sie einfach in einigen Anrufe an die glTexCoord * Familie von Funktionen. NeHe hat eine gute Anleitung, wie man mit Textur-Mapping, um loszulegen mit OpenGL.

Answer 2

Eigentlich gibt es eine Lösung ...

Sie erzeugen verwenden Textur wie diese Koordinaten

    glEnable(GL_TEXTURE_GEN_S); //enable texture coordinate generation
    glEnable(GL_TEXTURE_GEN_T);
    glBindTexture(GL_TEXTURE_2D, theTexture[2]);
    glutSolidCube(2);
    glDisable(GL_TEXTURE_GEN_S); //enable texture coordinate generation
    glDisable(GL_TEXTURE_GEN_T);

Answer 3

Nach dem GLUT-API-Dokumentation rel="nofollow:

  

[glutSolidCube erzeugt] Normalen geeignet für Beleuchtung, sondern erzeugt keine Texturkoordinaten (mit Ausnahme der Teekanne).