diff options
Diffstat (limited to 'src/primitives.cc')
-rw-r--r-- | src/primitives.cc | 119 |
1 files changed, 59 insertions, 60 deletions
diff --git a/src/primitives.cc b/src/primitives.cc index 5ba32fe..5180c16 100644 --- a/src/primitives.cc +++ b/src/primitives.cc @@ -34,6 +34,8 @@ #include "printutils.h" #include <assert.h> +#define F_MINIMUM 0.01 + enum primitive_type_e { CUBE, SPHERE, @@ -57,7 +59,6 @@ class PrimitiveNode : public AbstractPolyNode public: bool center; double x, y, z, h, r1, r2; - static const double F_MINIMUM = 0.01; double fn, fs, fa; primitive_type_e type; int convexity; @@ -106,13 +107,13 @@ AbstractNode *PrimitiveModule::evaluate(const Context *ctx, const ModuleInstanti node->fs = c.lookup_variable("$fs").num; node->fa = c.lookup_variable("$fa").num; - if (node->fs < PrimitiveNode::F_MINIMUM) { - PRINTF("WARNING: $fs too small - clamping to %f", PrimitiveNode::F_MINIMUM); - node->fs = PrimitiveNode::F_MINIMUM; + if (node->fs < F_MINIMUM) { + PRINTF("WARNING: $fs too small - clamping to %f", F_MINIMUM); + node->fs = F_MINIMUM; } - if (node->fa < PrimitiveNode::F_MINIMUM) { - PRINTF("WARNING: $fa too small - clamping to %f", PrimitiveNode::F_MINIMUM); - node->fa = PrimitiveNode::F_MINIMUM; + if (node->fa < F_MINIMUM) { + PRINTF("WARNING: $fa too small - clamping to %f", F_MINIMUM); + node->fa = F_MINIMUM; } @@ -219,6 +220,19 @@ int get_fragments_from_r(double r, double fn, double fs, double fa) return (int)ceil(fmax(fmin(360.0 / fa, r*M_PI / fs), 5)); } +struct point2d { + double x, y; +}; + +static void generate_circle(point2d *circle, double r, int fragments) +{ + for (int i=0; i<fragments; i++) { + double phi = (M_PI*2*i) / fragments; + circle[i].x = r*cos(phi); + circle[i].y = r*sin(phi); + } +} + PolySet *PrimitiveNode::render_polyset(render_mode_e) const { PolySet *p = new PolySet(); @@ -279,70 +293,66 @@ PolySet *PrimitiveNode::render_polyset(render_mode_e) const if (type == SPHERE && r1 > 0) { - struct point2d { - double x, y; - }; - struct ring_s { - int fragments; point2d *points; - double r, z; + double z; }; - int rings = get_fragments_from_r(r1, fn, fs, fa); + int fragments = get_fragments_from_r(r1, fn, fs, fa); + int rings = fragments/2; +// Uncomment the following three lines to enable experimental sphere tesselation +// if (rings % 2 == 0) rings++; // To ensure that the middle ring is at phi == 0 degrees + ring_s *ring = new ring_s[rings]; +// double offset = 0.5 * ((fragments / 2) % 2); for (int i = 0; i < rings; i++) { +// double phi = (M_PI * (i + offset)) / (fragments/2); double phi = (M_PI * (i + 0.5)) / rings; - ring[i].r = r1 * sin(phi); + double r = r1 * sin(phi); ring[i].z = r1 * cos(phi); - ring[i].fragments = get_fragments_from_r(ring[i].r, fn, fs, fa); - ring[i].points = new point2d[ring[i].fragments]; - for (int j = 0; j < ring[i].fragments; j++) { - phi = (M_PI*2*j) / ring[i].fragments; - ring[i].points[j].x = ring[i].r * cos(phi); - ring[i].points[j].y = ring[i].r * sin(phi); - } + ring[i].points = new point2d[fragments]; + generate_circle(ring[i].points, r, fragments); } p->append_poly(); - for (int i = 0; i < ring[0].fragments; i++) + for (int i = 0; i < fragments; i++) p->append_vertex(ring[0].points[i].x, ring[0].points[i].y, ring[0].z); for (int i = 0; i < rings-1; i++) { ring_s *r1 = &ring[i]; ring_s *r2 = &ring[i+1]; int r1i = 0, r2i = 0; - while (r1i < r1->fragments || r2i < r2->fragments) + while (r1i < fragments || r2i < fragments) { - if (r1i >= r1->fragments) + if (r1i >= fragments) goto sphere_next_r2; - if (r2i >= r2->fragments) + if (r2i >= fragments) goto sphere_next_r1; - if ((double)r1i / r1->fragments < - (double)r2i / r2->fragments) + if ((double)r1i / fragments < + (double)r2i / fragments) { sphere_next_r1: p->append_poly(); - int r1j = (r1i+1) % r1->fragments; + int r1j = (r1i+1) % fragments; p->insert_vertex(r1->points[r1i].x, r1->points[r1i].y, r1->z); p->insert_vertex(r1->points[r1j].x, r1->points[r1j].y, r1->z); - p->insert_vertex(r2->points[r2i % r2->fragments].x, r2->points[r2i % r2->fragments].y, r2->z); + p->insert_vertex(r2->points[r2i % fragments].x, r2->points[r2i % fragments].y, r2->z); r1i++; } else { sphere_next_r2: p->append_poly(); - int r2j = (r2i+1) % r2->fragments; + int r2j = (r2i+1) % fragments; p->append_vertex(r2->points[r2i].x, r2->points[r2i].y, r2->z); p->append_vertex(r2->points[r2j].x, r2->points[r2j].y, r2->z); - p->append_vertex(r1->points[r1i % r1->fragments].x, r1->points[r1i % r1->fragments].y, r1->z); + p->append_vertex(r1->points[r1i % fragments].x, r1->points[r1i % fragments].y, r1->z); r2i++; } } } p->append_poly(); - for (int i = 0; i < ring[rings-1].fragments; i++) + for (int i = 0; i < fragments; i++) p->insert_vertex(ring[rings-1].points[i].x, ring[rings-1].points[i].y, ring[rings-1].z); delete[] ring; @@ -361,44 +371,33 @@ sphere_next_r2: z2 = h; } - struct point2d { - double x, y; - }; - point2d *circle1 = new point2d[fragments]; point2d *circle2 = new point2d[fragments]; - for (int i=0; i<fragments; i++) { - double phi = (M_PI*2*i) / fragments; - if (r1 > 0) { - circle1[i].x = r1*cos(phi); - circle1[i].y = r1*sin(phi); - } else { - circle1[i].x = 0; - circle1[i].y = 0; - } - if (r2 > 0) { - circle2[i].x = r2*cos(phi); - circle2[i].y = r2*sin(phi); - } else { - circle2[i].x = 0; - circle2[i].y = 0; - } - } + generate_circle(circle1, r1, fragments); + generate_circle(circle2, r2, fragments); for (int i=0; i<fragments; i++) { int j = (i+1) % fragments; - if (r1 > 0) { + if (r1 == r2) { p->append_poly(); p->insert_vertex(circle1[i].x, circle1[i].y, z1); p->insert_vertex(circle2[i].x, circle2[i].y, z2); - p->insert_vertex(circle1[j].x, circle1[j].y, z1); - } - if (r2 > 0) { - p->append_poly(); - p->insert_vertex(circle2[i].x, circle2[i].y, z2); p->insert_vertex(circle2[j].x, circle2[j].y, z2); p->insert_vertex(circle1[j].x, circle1[j].y, z1); + } else { + if (r1 > 0) { + p->append_poly(); + p->insert_vertex(circle1[i].x, circle1[i].y, z1); + p->insert_vertex(circle2[i].x, circle2[i].y, z2); + p->insert_vertex(circle1[j].x, circle1[j].y, z1); + } + if (r2 > 0) { + p->append_poly(); + p->insert_vertex(circle2[i].x, circle2[i].y, z2); + p->insert_vertex(circle2[j].x, circle2[j].y, z2); + p->insert_vertex(circle1[j].x, circle1[j].y, z1); + } } } |