From: Rob Body (rdb++at++hrwallingford.co.uk)
Date: 07/02/2002 01:29:31
Hi Performers,
I have created a triangle mesh using Performer 2.5 and RedHat Linux 7.2 but
don't know how to add a texture to it or modify the vertex's at run time. I
have calculated the new height's of each vertex and modified
vtx_table[i][PF_Z] at run time but the new values aren't drawn.
Code to create the triangles
/*--------------------------------------------------------------------------
*/
DS_create_test_tris(pfScene *scene)
{
pfGroup *group;
pfGeode *geode;
pfGeoSet *gset = NULL;
pfGeoState *gstate = NULL;
void *arena = pfGetSharedArena();
int p;
int num_vtx;
int num_triangles;
int num_indices;
int *lengths;
pfVec3 *vtx_table;
ushort *index_table;
int num_col;
pfVec4 *colour;
ushort *col_index;
col_index = (ushort*) pfMalloc(sizeof(ushort) * 1, arena);
group = pfNewGroup();
geode = pfNewGeode();
gset = pfNewGSet(arena);
pfAddChild( scene, group);
pfAddChild(group, geode);
pfAddGSet(geode, gset);
num_vtx = 4; /* EXAMPLE */
/* Allocate memory for vertices in shared memory */
vtx_table = (pfVec3*) pfMalloc(sizeof(pfVec3) * num_vtx, arena);
vtx_table[0][PF_X] = 50.0;
vtx_table[0][PF_Y] = 50.0;
vtx_table[0][PF_Z] = 2.0;
vtx_table[1][PF_X] = 75.0;
vtx_table[1][PF_Y] = 50.0;
vtx_table[1][PF_Z] = 2.0;
vtx_table[2][PF_X] = 50.0;
vtx_table[2][PF_Y] = 75.0;
vtx_table[2][PF_Z] = 2.0;
vtx_table[3][PF_X] = 75.0;
vtx_table[3][PF_Y] = 75.0;
vtx_table[3][PF_Z] = 2.0;
num_triangles = 2;
num_indices = 3 * num_triangles;
index_table = (ushort*) pfMalloc(sizeof(ushort) * num_indices, arena);
/* For independent triangles */
index_table[0] = 0; /* Indexing starts at 0 */
index_table[1] = 1;
index_table[2] = 2;
index_table[3] = 2;
index_table[4] = 1;
index_table[5] = 3;
/* Set up the vertex info of the geoset */
pfGSetAttr(gset, PFGS_COORD3, PFGS_PER_VERTEX, vtx_table, index_table);
pfGSetPrimType(gset, PFGS_TRIS);
pfGSetNumPrims(gset, num_triangles); /* Number of triangles (our
primitive type) */
/* COLOUR */
/* ------ */
/* Use the same colour for all triangles */
num_col = 1;
colour = (pfVec4*) pfMalloc(sizeof(pfVec4) * num_col, arena);
colour[0][0] = 1.0;
colour[0][1] = 0.0;
colour[0][2] = 1.0;
colour[0][3] = 1.0;
/* Even though only 1 colour is used,
need a colour index table, since cannot mix indexed and non-indexed
data on a geoset */
col_index = (ushort*) pfMalloc(sizeof(ushort) * 1, arena);
col_index[0] = 0;
pfGSetAttr (gset, PFGS_COLOR4, PFGS_OVERALL, colour, col_index);
}
/*--------------------------------------------------------------------------
*/
In my loop I update the z values like this:
for (i = 0;i <= 16385;i++)
{
vtx_table[i][PF_Z] = rz[timecount][i];
}
Can anyone see what I have missed out and advise on how I add a texture to
the triangles. I would like to use one texture, repeated over the whole
triangular surface.
Thanks for any help.
Rob
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Rob Body
Simulator Manager
HR Mardyn
HR Wallingford
Howbery Park
Wallingford
Oxon
OX10 8BA
Tel +44 (0) 1491 822327
Fax +44 (0) 1491 832233
E-mail r.body++at++hrwallingford.co.uk <mailto:r.body++at++hrwallingford.co.uk>
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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This archive was generated by hypermail 2b29 : Tue Jul 02 2002 - 01:31:16 PDT