Cube also moved to glDrawElements

git-svn-id: https://svn.code.sf.net/p/freeglut/code/trunk@1145 7f0cb862-5218-0410-a997-914c9d46530a
This commit is contained in:
dcnieho 2012-03-16 03:14:23 +00:00
parent d3550b00d9
commit 833166240f

View File

@ -61,8 +61,7 @@
*/
/*
* General function for drawing geometry. As for all geometry we have no
/* General function for drawing geometry. As for all geometry we have no
* redundancy (or hardly any in the case of cones and cylinders) in terms
* of the vertex/normal combinations, we just use glDrawArrays.
* useWireMode controls the drawing of solids (false) or wire frame
@ -99,6 +98,73 @@ static unsigned int ipow (int x, unsigned int y)
return y==0? 1: y==1? x: (y%2? x: 1) * ipow(x*x, y/2);
}
/* -- stuff that can be cached -- */
/*
* In general, we build arrays with all vertices or normals.
* We cant compress this and use glDrawElements as all combinations of
* vertex and normals are unique.
*/
/* -- Cube -- */
#define CUBE_NUM_VERT 8
#define CUBE_NUM_FACES 6
#define CUBE_NUM_VERT_PER_FACE 4
#define CUBE_VERT_PER_TETR CUBE_NUM_FACES*CUBE_NUM_VERT_PER_FACE
#define CUBE_VERT_ELEM_PER_TETR CUBE_VERT_PER_TETR*3
/* Vertex Coordinates */
static GLdouble cube_v[CUBE_NUM_VERT][3] =
{
{ .5, .5, .5},
{-.5, .5, .5},
{-.5,-.5, .5},
{ .5,-.5, .5},
{ .5,-.5,-.5},
{ .5, .5,-.5},
{-.5, .5,-.5},
{-.5,-.5,-.5}
};
/* Normal Vectors */
static GLdouble cube_n[CUBE_NUM_FACES][3] =
{
{ 1.0, 0.0, 0.0},
{ 0.0, 1.0, 0.0},
{ 0.0, 0.0, 1.0},
{-1.0, 0.0, 0.0},
{ 0.0,-1.0, 0.0},
{ 0.0, 0.0,-1.0}
};
/* Vertex indices */
static GLubyte cube_vi[CUBE_NUM_FACES][CUBE_NUM_VERT_PER_FACE] =
{
{0,1,2,3}, {0,3,4,5}, {0,5,6,1}, {1,6,7,2}, {7,4,3,2}, {4,7,6,5}
};
/* Cache of input to glDrawArrays */
static GLboolean cubeCached = FALSE;
static double cube_verts[CUBE_VERT_ELEM_PER_TETR];
static double cube_norms[CUBE_VERT_ELEM_PER_TETR];
static void fghCubeGenerate()
{
int i,j;
for (i=0; i<CUBE_NUM_FACES; i++)
{
for (j=0; j<CUBE_NUM_VERT_PER_FACE; j++)
{
int idx = i*CUBE_NUM_VERT_PER_FACE*3+j*3;
cube_verts[idx ] = cube_v[cube_vi[i][j]][0];
cube_verts[idx+1] = cube_v[cube_vi[i][j]][1];
cube_verts[idx+2] = cube_v[cube_vi[i][j]][2];
cube_norms[idx ] = cube_n[i][0];
cube_norms[idx+1] = cube_n[i][1];
cube_norms[idx+2] = cube_n[i][2];
}
}
}
/* -- Tetrahedron -- */
/* Magic Numbers: r0 = ( 1, 0, 0 )
* r1 = ( -1/3, 2 sqrt(2) / 3, 0 )
* r2 = ( -1/3, - sqrt(2) / 3, sqrt(6) / 3 )
@ -107,33 +173,35 @@ static unsigned int ipow (int x, unsigned int y)
* Distance between any two points is 2 sqrt(6) / 3
*
* Normals: The unit normals are simply the negative of the coordinates of the point not on the surface.
*/
/* -- Tetrahedron -- */
*/
#define TETR_NUM_VERT 4
#define TETR_NUM_FACES 4
#define TETR_NUM_VERT_PER_FACE 3
#define TETR_VERT_PER_TETR TETR_NUM_FACES*TETR_NUM_VERT_PER_FACE
#define TETR_VERT_ELEM_PER_TETR TETR_VERT_PER_TETR*3
/* Vertex Coordinates */
static GLdouble tet_r[TETR_NUM_FACES][TETR_NUM_VERT_PER_FACE] =
static GLdouble tet_r[TETR_NUM_VERT][TETR_NUM_VERT_PER_FACE] =
{
{ 1.0, 0.0, 0.0 },
{ -0.333333333333, 0.942809041582, 0.0 },
{ -0.333333333333, -0.471404520791, 0.816496580928 },
{ -0.333333333333, -0.471404520791, -0.816496580928 }
};
/* Normal Vectors */
static GLdouble tet_n[CUBE_NUM_FACES][3] =
{
{ - 1.0, 0.0, 0.0 },
{ 0.333333333333, -0.942809041582, 0.0 },
{ 0.333333333333, 0.471404520791, -0.816496580928 },
{ 0.333333333333, 0.471404520791, 0.816496580928 }
};
/* Vertex indices */
static GLubyte tet_i[TETR_NUM_FACES][TETR_NUM_VERT_PER_FACE] =
{
{ 1, 3, 2 }, { 0, 2, 3 }, { 0, 3, 1 }, { 0, 1, 2 }
};
/* Normal indices */
static GLubyte tet_n[TETR_NUM_FACES] =
{
0, 1, 2, 3
};
/* Cache of input to glDrawArrays */
static GLboolean tetrCached = FALSE;
@ -144,11 +212,11 @@ static void fghTetrahedronGenerate()
{
int i,j;
/*
* Build array with vertices from vertex coordinates and vertex indices
* Do same for normals.
* Need to do this because of different normals at shared vertices
* (and because normals' coordinates need to be negated).
*/
* Build array with vertices from vertex coordinates and vertex indices
* Do same for normals.
* Need to do this because of different normals at shared vertices
* (and because normals' coordinates need to be negated).
*/
for (i=0; i<TETR_NUM_FACES; i++)
{
for (j=0; j<TETR_NUM_VERT_PER_FACE; j++)
@ -158,9 +226,9 @@ static void fghTetrahedronGenerate()
tetr_verts[idx+1] = tet_r[tet_i[i][j]][1];
tetr_verts[idx+2] = tet_r[tet_i[i][j]][2];
tetr_norms[idx ] = -tet_r[tet_n[i]][0];
tetr_norms[idx+1] = -tet_r[tet_n[i]][1];
tetr_norms[idx+2] = -tet_r[tet_n[i]][2];
tetr_norms[idx ] = tet_n[i][0];
tetr_norms[idx+1] = tet_n[i][1];
tetr_norms[idx+2] = tet_n[i][2];
}
}
}
@ -180,9 +248,9 @@ static void fghSierpinskiSpongeGenerate ( int numLevels, GLdouble offset[3], GLd
vertices[idx+1] = offset[1] + scale * tet_r[tet_i[i][j]][1];
vertices[idx+2] = offset[2] + scale * tet_r[tet_i[i][j]][2];
normals[idx ] = -tet_r[tet_n[i]][0];
normals[idx+1] = -tet_r[tet_n[i]][1];
normals[idx+2] = -tet_r[tet_n[i]][2];
normals [idx ] = -tet_r[i][0];
normals [idx+1] = -tet_r[i][1];
normals [idx+2] = -tet_r[i][2];
}
}
}
@ -257,6 +325,20 @@ static void fghCircleTable(double **sint,double **cost,const int n)
/* -- INTERNAL DRAWING functions to avoid code duplication ------------- */
static void fghCube( GLdouble dSize, GLboolean useWireMode )
{
if (!cubeCached)
fghCubeGenerate();
if (dSize!=1.)
{
/* Need to build new */
fghDrawGeometry(GL_QUADS,cube_verts,cube_norms,CUBE_VERT_PER_TETR,useWireMode);
}
else
fghDrawGeometry(GL_QUADS,cube_verts,cube_norms,CUBE_VERT_PER_TETR,useWireMode);
}
static void fghTetrahedron( GLboolean useWireMode )
{
if (!tetrCached)
@ -291,56 +373,6 @@ static void fghSierpinskiSponge ( int numLevels, GLdouble offset[3], GLdouble sc
/* -- INTERFACE FUNCTIONS ---------------------------------------------- */
/*
* Draws a wireframed cube. Code contributed by Andreas Umbach <marvin@dataway.ch>
*/
void FGAPIENTRY glutWireCube( GLdouble dSize )
{
double size = dSize * 0.5;
FREEGLUT_EXIT_IF_NOT_INITIALISED ( "glutWireCube" );
# define V(a,b,c) glVertex3d( a size, b size, c size );
# define N(a,b,c) glNormal3d( a, b, c );
/* PWO: I dared to convert the code to use macros... */
glBegin( GL_LINE_LOOP ); N( 1.0, 0.0, 0.0); V(+,-,+); V(+,-,-); V(+,+,-); V(+,+,+); glEnd();
glBegin( GL_LINE_LOOP ); N( 0.0, 1.0, 0.0); V(+,+,+); V(+,+,-); V(-,+,-); V(-,+,+); glEnd();
glBegin( GL_LINE_LOOP ); N( 0.0, 0.0, 1.0); V(+,+,+); V(-,+,+); V(-,-,+); V(+,-,+); glEnd();
glBegin( GL_LINE_LOOP ); N(-1.0, 0.0, 0.0); V(-,-,+); V(-,+,+); V(-,+,-); V(-,-,-); glEnd();
glBegin( GL_LINE_LOOP ); N( 0.0,-1.0, 0.0); V(-,-,+); V(-,-,-); V(+,-,-); V(+,-,+); glEnd();
glBegin( GL_LINE_LOOP ); N( 0.0, 0.0,-1.0); V(-,-,-); V(-,+,-); V(+,+,-); V(+,-,-); glEnd();
# undef V
# undef N
}
/*
* Draws a solid cube. Code contributed by Andreas Umbach <marvin@dataway.ch>
*/
void FGAPIENTRY glutSolidCube( GLdouble dSize )
{
double size = dSize * 0.5;
FREEGLUT_EXIT_IF_NOT_INITIALISED ( "glutSolidCube" );
# define V(a,b,c) glVertex3d( a size, b size, c size );
# define N(a,b,c) glNormal3d( a, b, c );
/* PWO: Again, I dared to convert the code to use macros... */
glBegin( GL_QUADS );
N( 1.0, 0.0, 0.0); V(+,-,+); V(+,-,-); V(+,+,-); V(+,+,+);
N( 0.0, 1.0, 0.0); V(+,+,+); V(+,+,-); V(-,+,-); V(-,+,+);
N( 0.0, 0.0, 1.0); V(+,+,+); V(-,+,+); V(-,-,+); V(+,-,+);
N(-1.0, 0.0, 0.0); V(-,-,+); V(-,+,+); V(-,+,-); V(-,-,-);
N( 0.0,-1.0, 0.0); V(-,-,+); V(-,-,-); V(+,-,-); V(+,-,+);
N( 0.0, 0.0,-1.0); V(-,-,-); V(-,+,-); V(+,+,-); V(+,-,-);
glEnd();
# undef V
# undef N
}
/*
* Draws a solid sphere
@ -1263,7 +1295,19 @@ void FGAPIENTRY glutSolidRhombicDodecahedron( void )
/* -- INTERFACE FUNCTIONS -------------------------------------------------- */
/*
* Draws a wireframed cube.
*/
void FGAPIENTRY glutWireCube( GLdouble dSize )
{
FREEGLUT_EXIT_IF_NOT_INITIALISED ( "glutWireCube" );
fghCube( dSize, TRUE );
}
void FGAPIENTRY glutSolidCube( GLdouble dSize )
{
FREEGLUT_EXIT_IF_NOT_INITIALISED ( "glutSolidCube" );
fghCube( dSize, FALSE );
}
void FGAPIENTRY glutWireTetrahedron( void )
{