The open source OpenXR runtime
d/ns: possibly fix mesh calculation
also fix flipped tracking tracking
+32
-19
+32
-19
src/xrt/drivers/north_star/ns_hmd.c
+32
-19
src/xrt/drivers/north_star/ns_hmd.c
···
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305
float v,
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306
struct xrt_uv_triplet *result)
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{
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+
u = 1.0 - u; // Not sure why these are necessary: somewhat concerning.
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+
v = 1.0 - v; // They make it work though, so hey.
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+
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struct ns_hmd *ns = ns_hmd(xdev);
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310
-
float x = 0.0f;
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-
float y = 0.0f;
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-
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-
u = 1.0 - u;
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-
v = 1.0 - v;
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-
316
-
float L = ns->eye_configs_v2[view].fov.angle_left;
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-
float R = ns->eye_configs_v2[view].fov.angle_right;
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-
float T = ns->eye_configs_v2[view].fov.angle_up;
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-
float B = ns->eye_configs_v2[view].fov.angle_down;
320
-
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float x_ray =
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ns_v2_polyval2d(u, v, ns->eye_configs_v2[view].x_coefficients);
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float y_ray =
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ns_v2_polyval2d(u, v, ns->eye_configs_v2[view].y_coefficients);
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-
x = (x_ray + L) / (L - R);
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-
y = (y_ray + T) / (T - B);
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318
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+
float left_ray_bound = tan(ns->eye_configs_v2[view].fov.angle_left);
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+
float right_ray_bound = tan(ns->eye_configs_v2[view].fov.angle_right);
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+
float up_ray_bound = tan(ns->eye_configs_v2[view].fov.angle_up);
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+
float down_ray_bound = tan(ns->eye_configs_v2[view].fov.angle_down);
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323
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-
result->r.x = x;
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result->r.y = y;
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-
result->g.x = x;
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result->g.y = y;
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result->b.x = x;
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result->b.y = y;
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+
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+
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+
// Both of these are very concise implementations of map() in Arduino.
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// https://www.arduino.cc/reference/en/language/functions/math/map/
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// In other words, a one-axis linear transformation.
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+
// I wish I was better at linear algebra so I had could describe this
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// better
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+
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+
// map(x_ray, left_ray_bound, right_ray_bound, 0, 1)
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float u_eye =
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+
(x_ray + right_ray_bound) / (right_ray_bound - left_ray_bound);
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+
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// map(y_ray, down_ray_bound, up_ray_bound, 0, 1)
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float v_eye = (y_ray + up_ray_bound) / (up_ray_bound - down_ray_bound);
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+
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+
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// boilerplate, put the UV coordinates in all the RGB slots
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result->r.x = u_eye;
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result->r.y = v_eye;
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result->g.x = u_eye;
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result->g.y = v_eye;
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result->b.x = u_eye;
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result->b.y = v_eye;
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+
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return true;
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}
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···
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569
ns->base.hmd->distortion.preferred =
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XRT_DISTORTION_MODEL_COMPUTE;
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ns->base.compute_distortion = ns_v2_mesh_calc;
572
+
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} else {
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// V1
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ns->base.get_view_pose = ns_hmd_get_view_pose;