triquadd.c

Intro/: Directory containing introductory examples. HelloWorld.c A simple program that draws a bo

#include <phigs.h>			/* get HP-PHIGS definitions for C */
#include <stdio.h>			/* get standard I/O definitions */
#include <math.h>			/* link with library "-lm" */

#define	SetGcolr(Var,Rd,Gr,Bl)	Var.colr_type = PCOLR_RGB;		\
				Var.colr_value.colr_rep.rgb.red   = Rd;	\
				Var.colr_value.colr_rep.rgb.green = Gr;	\
				Var.colr_value.colr_rep.rgb.blue  = Bl

Pgcolr		GWhite, GRed;			/* colours in Pgcolr format */
static Prgb	Red    = {1.0, 0.0, 0.0};	/* RGB for red */
static Prgb	Yellow = {1.0, 1.0, 0.0};	/* RGB for yellow */

main()					/* file "TriQuadD.c" */
{
    Pint	WorkstnID = 1;		/* workstation identifier */
    Pint	ConnID;			/* connection identifier */
    Pint	WorkstnType = POIDDX;	/* out/in, direct, dbl bfr, Xwindow */
    Pint	Scene=1, Strip=2, Mesh=3;	/* structure IDs */

    /*--- initialize variables ---------------------------------------------*/
    SetGcolr(GWhite,  1.0, 1.0, 1.0);
    SetGcolr(GRed,    1.0, 0.0, 0.0);
    /*--- start up PHIGS ---------------------------------------------------*/
    popen_phigs((char *) stderr, 0);	/* errors go to "stderr" */
    pescape_u4("/dev/screen/phigs_window", &ConnID);
    popen_ws(WorkstnID, (void *) ConnID, WorkstnType);
    pescape_u250(WorkstnID, 0);		/* direct colour environment */
    CreateQuadrilateralMesh(Mesh);
    CreateTriangleStrip(Strip);
    /*--- define the structure for the whole scene -------------------------*/
    popen_struct(Scene);
    pset_int_style(PSTYLE_SOLID);
    pset_int_colr(&GRed);
    pset_edge_flag(PEDGE_ON);
    pset_edge_colr(&GWhite);
    pset_int_shad_method(PINT_SHAD_METHOD_COLR);
    pexec_struct(Mesh);
    pexec_struct(Strip);
    pclose_struct();
    ppost_struct(WorkstnID, Scene, 1.0);
    pclose_ws(WorkstnID);
    pclose_phigs();
}
/****************************************************************************/
CreateQuadrilateralMesh(Mesh)
Pint	Mesh;
{
    Pvertex3_array	QuadMesh;	/* \				   */
    Ppoint3		QuadMeshPts[30];/*  > main data structure for mesh */
    Prgb		VertexColrs[30];/* /				   */
    Pfacet_array	Facets;		/* facet data holder */
    Prgb		FacetColrs[18];	/* facets' RGB array */
    Pvec3		Vector;		/* for various translations */
    Pmatrix3		xform;		/* transformation matrix */
    Pint		Error;		/* error-return variable */
    int			I;		/* loop control variable */
    
    /*--- define the vertices for the quadrilateral mesh -------------------*/
    for (I = 0; I < 30; I++) {
	QuadMeshPts[I].x = (I % 10) * 0.04;
	QuadMeshPts[I].y = 0.2 - (I / 10) * 0.1;
	QuadMeshPts[I].z = 0.5;
    }
    /*--- define the facet colours for the quadrilateral mesh --------------*/
    for (I = 0; I < 18; I++) {
	if ((I % 9) % 2)
	    FacetColrs[I] = Yellow;
	else
	    FacetColrs[I] =   Red;
    }
    /*--- define the vertex colours for the quadrilateral mesh -------------*/
    for (I = 0; I < 30; I++) {
	if ((I / 10) % 2)
	    VertexColrs[I] =   Yellow;
	else
	    VertexColrs[I] =   Red;
    }
    /*--- define the structure that does the quadrilateral mesh ------------*/
    popen_struct(Mesh);
    QuadMesh.dims.size_x = 10;
    QuadMesh.dims.size_y = 3;
    QuadMesh.num_data_per_vertex = 0;
    QuadMesh.vertex_points = QuadMeshPts;
    QuadMesh.vertex_colrvs.colr_reps.rgb = NULL;
    QuadMesh.vertex_norms = NULL;
    QuadMesh.vertex_data = NULL;
    Facets.dims.size_x = 2;
    Facets.dims.size_y = 9;
    Facets.num_data_per_facet = 0;
    Facets.facet_colrvs.colr_reps.rgb = FacetColrs;
    Facets.facet_norms = NULL;
    Facets.facet_data = NULL;
    /*--- first: use interior colour ---------------------------------------*/
    Vector.delta_x = 0.08, Vector.delta_y = 0.76, Vector.delta_z = 0.0;
    ptranslate3(&Vector, &Error, xform);
    pset_local_tran3(xform, PTYPE_REPLACE);
    pquad_mesh3_data(PCOLR_RGB, NULL, NULL, &QuadMesh);
    /*--- second: use facet colour -----------------------------------------*/
    Vector.delta_x = 0.52, Vector.delta_y = 0.76, Vector.delta_z = 0.0;
    ptranslate3(&Vector, &Error, xform);
    pset_local_tran3(xform, PTYPE_REPLACE);
    pquad_mesh3_data(PCOLR_RGB, &Facets, NULL, &QuadMesh);
    /*--- third: use vertex colour -----------------------------------------*/
    QuadMesh.vertex_colrvs.colr_reps.rgb = VertexColrs;
    Vector.delta_x = 0.52, Vector.delta_y = 0.53, Vector.delta_z = 0.0;
    ptranslate3(&Vector, &Error, xform);
    pset_local_tran3(xform, PTYPE_REPLACE);
    pquad_mesh3_data(PCOLR_RGB, NULL, NULL, &QuadMesh);
    pclose_struct();
}
/****************************************************************************/
CreateTriangleStrip(Strip)
Pint	Strip;
{
    Pvertex3_list	TriStrip1;		/* \  for the data for the */
    Ppoint3		TriStripPts1[20];	/*  > top one of each pair */
    Prgb		VertexColrs1[20];	/* /  of triangle strips   */
    Pvertex3_list	TriStrip2;		/* \  for the data for the */
    Ppoint3		TriStripPts2[20];	/*  > bottom one of each   */
    Prgb		VertexColrs2[20];	/* /  pair of tri. strips  */
    Pfacet_list		Facets;		/* facet data holder */
    Prgb		FacetColrs[18];	/* facets' RGB array */
    Pvec3		Vector;		/* for various translations */
    Pmatrix3		xform;		/* transformation matrix */
    Pint		Error;		/* error-return variable */
    int			I;		/* loop control variable */
    
    /*--- define the points for the triangle strips ------------------------*/
    for (I = 0; I < 20; I++) {
	TriStripPts1[I].x = (I / 2) * 0.04;
	TriStripPts1[I].y = (1 - I % 2) * 0.1;
	TriStripPts1[I].z = 0.5;
	TriStripPts2[I].x = TriStripPts1[I].x;
	TriStripPts2[I].y = TriStripPts1[I].y + 0.1;
	TriStripPts2[I].z = 0.5;
    }
    /*--- define the facet colours for the triangle strips -----------------*/
    for (I = 0; I < 18; I++) {
	if (I % 4 <= 1)
	    FacetColrs[I] =   Red;
	else
	    FacetColrs[I] =   Yellow;
    }
    /*--- define the vertex colours for the triangle strips ----------------*/
    for (I = 0; I < 20; I++) {
	if (I % 2) {
	    VertexColrs1[I] =   Red;
	    VertexColrs2[I] =   Yellow;
	}
	else {
	    VertexColrs1[I] =   Yellow;
	    VertexColrs2[I] =   Red;
	}
    }
    /*=== define the structure that does the triangle strips ===============*/
    popen_struct(Strip);
    TriStrip1.num_vertices = 20;
    TriStrip2.num_vertices = 20;
    TriStrip1.num_data_per_vertex = 0;
    TriStrip1.num_data_per_vertex = 0;
    TriStrip1.vertex_points = TriStripPts1;
    TriStrip2.vertex_points = TriStripPts2;
    TriStrip1.vertex_colrvs.colr_reps.rgb = NULL;
    TriStrip2.vertex_colrvs.colr_reps.rgb = NULL;
    TriStrip1.vertex_norms = NULL;
    TriStrip2.vertex_norms = NULL;
    TriStrip1.vertex_data = NULL;
    TriStrip2.vertex_data = NULL;
    Facets.num_facets = 18;
    Facets.num_data_per_facet = 0;
    Facets.facet_colrvs.colr_reps.rgb = FacetColrs;
    Facets.facet_norms = NULL;
    Facets.facet_data = NULL;
    /*--- first: use interior colour ---------------------------------------*/
    Vector.delta_x = 0.08, Vector.delta_y = 0.28, Vector.delta_z = 0.0;
    ptranslate3(&Vector, &Error, xform);
    pset_local_tran3(xform, PTYPE_REPLACE);
    ptri_strip3_data(PCOLR_RGB, NULL, NULL, &TriStrip1);
    ptri_strip3_data(PCOLR_RGB, NULL, NULL, &TriStrip2);
    /*--- second: use facet colour -----------------------------------------*/
    Vector.delta_x = 0.52, Vector.delta_y = 0.28, Vector.delta_z = 0.0;
    ptranslate3(&Vector, &Error, xform);
    pset_local_tran3(xform, PTYPE_REPLACE);
    ptri_strip3_data(PCOLR_RGB, &Facets, NULL, &TriStrip1);
    ptri_strip3_data(PCOLR_RGB, &Facets, NULL, &TriStrip2);
    /*--- third: use vertex colour -----------------------------------------*/
    TriStrip1.vertex_colrvs.colr_reps.rgb = VertexColrs1;
    TriStrip2.vertex_colrvs.colr_reps.rgb = VertexColrs2;
    Vector.delta_x = 0.52, Vector.delta_y = 0.05, Vector.delta_z = 0.0;
    ptranslate3(&Vector, &Error, xform);
    pset_local_tran3(xform, PTYPE_REPLACE);
    ptri_strip3_data(PCOLR_RGB, NULL, NULL, &TriStrip1);
    ptri_strip3_data(PCOLR_RGB, NULL, NULL, &TriStrip2);
    pclose_struct();
}