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-rw-r--r--src/o3d/tri_deriv_vertex.cpp321
1 files changed, 321 insertions, 0 deletions
diff --git a/src/o3d/tri_deriv_vertex.cpp b/src/o3d/tri_deriv_vertex.cpp
new file mode 100644
index 0000000..3605b51
--- /dev/null
+++ b/src/o3d/tri_deriv_vertex.cpp
@@ -0,0 +1,321 @@
+#include "o3d/tri_deriv_vertex.h"
+#include <vector>
+#include "math/vector.h"
+#include "o3d/deriv_vertex.h"
+
+using namespace engine::o3d;
+
+TriangleDerivedVertex4::TriangleDerivedVertex4(DerivedVertex4 derived_vertex1, DerivedVertex4 derived_vertex2, DerivedVertex4 derived_vertex3)
+ : derived_vertex1{derived_vertex1}, derived_vertex2{derived_vertex2}, derived_vertex3{derived_vertex3} {
+}
+
+#define P1_OUT 1
+#define P2_OUT 2
+#define P3_OUT 4
+static void _perspective_crop_x(std::vector<TriangleDerivedVertex4>& tris, TriangleDerivedVertex4 t, int n, float x) {
+ switch (n) {
+ case 0:
+ tris.push_back(t);
+ break;
+ case P1_OUT:
+ case P2_OUT:
+ case P3_OUT:
+ case P2_OUT | P3_OUT:
+ case P1_OUT | P3_OUT:
+ case P1_OUT | P2_OUT:
+ {
+ DerivedVertex4* q1;
+ DerivedVertex4* q2;
+ DerivedVertex4* q3;
+ switch (n) {
+ case P1_OUT:
+ case P2_OUT | P3_OUT:
+ q1 = &t.derived_vertex1;
+ q2 = &t.derived_vertex2;
+ q3 = &t.derived_vertex3;
+ break;
+ case P2_OUT:
+ case P1_OUT | P3_OUT:
+ q1 = &t.derived_vertex2;
+ q2 = &t.derived_vertex1;
+ q3 = &t.derived_vertex3;
+ break;
+ case P3_OUT:
+ case P1_OUT | P2_OUT:
+ q1 = &t.derived_vertex3;
+ q2 = &t.derived_vertex2;
+ q3 = &t.derived_vertex1;
+ break;
+ }
+ engine::math::Vector4 dq2 = q1->point - q2->point;
+ float fac2 = (x - q2->point.x) / dq2.x;
+ float r2w = 1.f / (fac2 / q1->point.w + (1.f - fac2) / q2->point.w);
+ float fac2_b = r2w * fac2 / q1->point.w;
+ DerivedVertex4 r2{
+ {
+ x,
+ q2->point.y + fac2 * dq2.y,
+ fac2_b * q1->point.z + (1.f - fac2_b) * q2->point.z,
+ r2w
+ },
+ fac2_b * q1->b0 + (1.f - fac2_b) * q2->b0,
+ fac2_b * q1->b1 + (1.f - fac2_b) * q2->b1
+ };
+ engine::math::Vector4 dq3 = q1->point - q3->point;
+ float fac3 = (x - q3->point.x) / dq3.x;
+ float r3w = 1.f / (fac3 / q1->point.w + (1.f - fac3) / q3->point.w);
+ float fac3_b = r3w * fac3 / q1->point.w;
+ DerivedVertex4 r3{
+ {
+ x,
+ q3->point.y + fac3 * dq3.y,
+ fac3_b * q1->point.z + (1.f - fac3_b) * q3->point.z,
+ r3w
+ },
+ fac3_b * q1->b0 + (1.f - fac3_b) * q3->b0,
+ fac3_b * q1->b1 + (1.f - fac3_b) * q3->b1
+ };
+ switch (n) {
+ case P1_OUT:
+ tris.push_back({r3, *q2, *q3});
+ tris.push_back({r3, r2, *q2});
+ break;
+ case P2_OUT:
+ tris.push_back({r2, *q3, *q2});
+ tris.push_back({r2, r3, *q3});
+ break;
+ case P3_OUT:
+ tris.push_back({r2, *q3, *q2});
+ tris.push_back({r2, r3, *q3});
+ break;
+ case P2_OUT | P3_OUT:
+ tris.push_back({*q1, r2, r3});
+ break;
+ case P1_OUT | P3_OUT:
+ tris.push_back({*q1, r3, r2});
+ break;
+ case P1_OUT | P2_OUT:
+ tris.push_back({*q1, r3, r2});
+ break;
+ }
+ }
+ break;
+ case P1_OUT | P2_OUT | P3_OUT:
+ break;
+ }
+}
+
+static void _perspective_crop_y(std::vector<TriangleDerivedVertex4>& tris, TriangleDerivedVertex4 t, int n, float y) {
+ switch (n) {
+ case 0:
+ tris.push_back(t);
+ break;
+ case P1_OUT:
+ case P2_OUT:
+ case P3_OUT:
+ case P2_OUT | P3_OUT:
+ case P1_OUT | P3_OUT:
+ case P1_OUT | P2_OUT:
+ {
+ DerivedVertex4* q1;
+ DerivedVertex4* q2;
+ DerivedVertex4* q3;
+ switch (n) {
+ case P1_OUT:
+ case P2_OUT | P3_OUT:
+ q1 = &t.derived_vertex1;
+ q2 = &t.derived_vertex2;
+ q3 = &t.derived_vertex3;
+ break;
+ case P2_OUT:
+ case P1_OUT | P3_OUT:
+ q1 = &t.derived_vertex2;
+ q2 = &t.derived_vertex1;
+ q3 = &t.derived_vertex3;
+ break;
+ case P3_OUT:
+ case P1_OUT | P2_OUT:
+ q1 = &t.derived_vertex3;
+ q2 = &t.derived_vertex2;
+ q3 = &t.derived_vertex1;
+ break;
+ }
+ engine::math::Vector4 dq2 = q1->point - q2->point;
+ float fac2 = (y - q2->point.y) / dq2.y;
+ float r2w = 1.f / (fac2 / q1->point.w + (1.f - fac2) / q2->point.w);
+ float fac2_b = r2w * fac2 / q1->point.w;
+ DerivedVertex4 r2{
+ {
+ q2->point.x + fac2 * dq2.x,
+ y,
+ fac2_b * q1->point.z + (1.f - fac2_b) * q2->point.z,
+ r2w
+ },
+ fac2_b * q1->b0 + (1.f - fac2_b) * q2->b0,
+ fac2_b * q1->b1 + (1.f - fac2_b) * q2->b1
+ };
+ engine::math::Vector4 dq3 = q1->point - q3->point;
+ float fac3 = (y - q3->point.y) / dq3.y;
+ float r3w = 1.f / (fac3 / q1->point.w + (1.f - fac3) / q3->point.w);
+ float fac3_b = r3w * fac3 / q1->point.w;
+ DerivedVertex4 r3{
+ {
+ q3->point.x + fac3 * dq3.x,
+ y,
+ fac3_b * q1->point.z + (1.f - fac3_b) * q3->point.z,
+ r3w
+ },
+ fac3_b * q1->b0 + (1.f - fac3_b) * q3->b0,
+ fac3_b * q1->b1 + (1.f - fac3_b) * q3->b1
+ };
+ switch (n) {
+ case P1_OUT:
+ tris.push_back({r3, *q2, *q3});
+ tris.push_back({r3, r2, *q2});
+ break;
+ case P2_OUT:
+ tris.push_back({r2, *q3, *q2});
+ tris.push_back({r2, r3, *q3});
+ break;
+ case P3_OUT:
+ tris.push_back({r2, *q3, *q2});
+ tris.push_back({r2, r3, *q3});
+ break;
+ case P2_OUT | P3_OUT:
+ tris.push_back({*q1, r2, r3});
+ break;
+ case P1_OUT | P3_OUT:
+ tris.push_back({*q1, r3, r2});
+ break;
+ case P1_OUT | P2_OUT:
+ tris.push_back({*q1, r3, r2});
+ break;
+ }
+ }
+ break;
+ case P1_OUT | P2_OUT | P3_OUT:
+ break;
+ }
+}
+
+std::vector<TriangleDerivedVertex4> TriangleDerivedVertex4::perspective_crop_xy_out(float x1, float x2, float y1, float y2) const {
+ std::vector<TriangleDerivedVertex4> tris_final;
+ std::vector<TriangleDerivedVertex4> tris1;
+ _perspective_crop_x(tris1, *this, (derived_vertex1.point.x < x1) | ((derived_vertex2.point.x < x1) << 1) | ((derived_vertex3.point.x < x1) << 2), x1);
+ for (auto t1 : tris1) {
+ std::vector<TriangleDerivedVertex4> tris2;
+ _perspective_crop_x(tris2, t1, (t1.derived_vertex1.point.x > x2) | ((t1.derived_vertex2.point.x > x2) << 1) | ((t1.derived_vertex3.point.x > x2) << 2), x2);
+ for (auto t2 : tris2) {
+ std::vector<TriangleDerivedVertex4> tris3;
+ _perspective_crop_y(tris3, t2, (t2.derived_vertex1.point.y < y1) | ((t2.derived_vertex2.point.y < y1) << 1) | ((t2.derived_vertex3.point.y < y1) << 2), y1);
+ for (auto t3 : tris3)
+ _perspective_crop_y(tris_final, t3, (t3.derived_vertex1.point.y > y2) | ((t3.derived_vertex2.point.y > y2) << 1) | ((t3.derived_vertex3.point.y > y2) << 2), y2);
+ }
+ }
+ return tris_final;
+}
+
+static void _crop_z(std::vector<TriangleDerivedVertex4>& tris, TriangleDerivedVertex4 t, int n, float z) {
+ switch (n) {
+ case 0:
+ tris.push_back(t);
+ break;
+ case P1_OUT:
+ case P2_OUT:
+ case P3_OUT:
+ case P2_OUT | P3_OUT:
+ case P1_OUT | P3_OUT:
+ case P1_OUT | P2_OUT:
+ {
+ DerivedVertex4* q1;
+ DerivedVertex4* q2;
+ DerivedVertex4* q3;
+ switch (n) {
+ case P1_OUT:
+ case P2_OUT | P3_OUT:
+ q1 = &t.derived_vertex1;
+ q2 = &t.derived_vertex2;
+ q3 = &t.derived_vertex3;
+ break;
+ case P2_OUT:
+ case P1_OUT | P3_OUT:
+ q1 = &t.derived_vertex2;
+ q2 = &t.derived_vertex1;
+ q3 = &t.derived_vertex3;
+ break;
+ case P3_OUT:
+ case P1_OUT | P2_OUT:
+ q1 = &t.derived_vertex3;
+ q2 = &t.derived_vertex2;
+ q3 = &t.derived_vertex1;
+ break;
+ }
+ engine::math::Vector4 dq2 = q1->point - q2->point;
+ float fac2 = (z - q2->point.z) / dq2.z;
+ DerivedVertex4 r2{
+ {
+ q2->point.x + fac2 * dq2.x,
+ q2->point.y + fac2 * dq2.y,
+ z,
+ q2->point.w + fac2 * dq2.w
+ },
+ fac2 * q1->b0 + (1.f - fac2) * q2->b0,
+ fac2 * q1->b1 + (1.f - fac2) * q2->b1
+ };
+ engine::math::Vector4 dq3 = q1->point - q3->point;
+ float fac3 = (z - q3->point.z) / dq3.z;
+ DerivedVertex4 r3{
+ {
+ q3->point.x + fac3 * dq3.x,
+ q3->point.y + fac3 * dq3.y,
+ z,
+ q3->point.w + fac3 * dq3.w
+ },
+ fac3 * q1->b0 + (1.f - fac3) * q3->b0,
+ fac3 * q1->b1 + (1.f - fac3) * q3->b1
+ };
+ switch (n) {
+ case P1_OUT:
+ tris.push_back({r3, *q2, *q3});
+ tris.push_back({r3, r2, *q2});
+ break;
+ case P2_OUT:
+ tris.push_back({r2, *q3, *q2});
+ tris.push_back({r2, r3, *q3});
+ break;
+ case P3_OUT:
+ tris.push_back({r2, *q3, *q2});
+ tris.push_back({r2, r3, *q3});
+ break;
+ case P2_OUT | P3_OUT:
+ tris.push_back({*q1, r2, r3});
+ break;
+ case P1_OUT | P3_OUT:
+ tris.push_back({*q1, r3, r2});
+ break;
+ case P1_OUT | P2_OUT:
+ tris.push_back({*q1, r3, r2});
+ break;
+ }
+ }
+ break;
+ case P1_OUT | P2_OUT | P3_OUT:
+ break;
+ }
+}
+
+std::vector<TriangleDerivedVertex4> TriangleDerivedVertex4::crop_z_out(float z1, float z2) const {
+ std::vector<TriangleDerivedVertex4> tris;
+ _crop_z(tris, *this, (derived_vertex1.point.z < z1) | ((derived_vertex2.point.z < z1) << 1) | ((derived_vertex3.point.z < z1) << 2), z1);
+ std::vector<TriangleDerivedVertex4> tris2;
+ for (auto t : tris)
+ _crop_z(tris2, t, (t.derived_vertex1.point.z > z2) | ((t.derived_vertex2.point.z > z2) << 1) | ((t.derived_vertex3.point.z > z2) << 2), z2);
+ return tris2;
+}
+#undef P1_OUT
+#undef P2_OUT
+#undef P3_OUT
+
+TriangleDerivedVertex4 TriangleDerivedVertex4::div_by_w() const {
+ return {derived_vertex1.div_by_w(), derived_vertex2.div_by_w(), derived_vertex3.div_by_w()};
+}
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