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Fix the assert triggering sometimes in the raytrace grid traversal.

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King_DuckZ 2017-07-23 04:37:25 +01:00
parent b0806e9e1c
commit 084c4d64da
1 changed files with 34 additions and 29 deletions
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63
src/gamelib/grid_raytrace.cpp
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@ -27,6 +27,7 @@
#include <cmath>
#include <cfloat>
#include <algorithm>
#include <cfloat>
namespace curry {
#if !defined(BUILD_TESTING)
@ -104,46 +105,50 @@ namespace curry {
const vec2f& u = parFrom;
const vec2f v = parTo - parFrom;
//vec2f step(fsgn(v.x()), fsgn(v.y()));
const auto delta = tile_size / v;
auto max = delta * (vec2f(1.0f) - frac(u / tile_size));
//vec2us start = pixel_to_world_tile(parWorld, u);
//const auto next_tile_boundary = (step + abs(step)) / 2.0f;
//const auto max = vec2f(
// segment_intersection(
// u,
// v,
// vec2f(static_cast<float>(start.x() + next_tile_boundary.x()), 0.0f),
// vec2f(0.0f, static_cast<float>(parWorld.world_size().y()) * tile_size.y())
// ),
// segment_intersection(
// u,
// v,
// vec2f(0.0f, static_cast<float>(start.y()) + next_tile_boundary.y()),
// vec2f(static_cast<float>(parWorld.world_size().x()) * tile_size.x(), 0.0f)
// )
//);
//const auto delta = vec2f(
// std::isinf(max.x()) ? 0.0f : tile_size.x() / dot(vec2f(1.0f, 0.0f), v * inv_length(v)),
// 0.0f //std::isinf(max.y()) ? 0.0f : tile_size.y() /
//);
const auto delta = tile_size / abs(v);
const auto fr = frac(u / tile_size);
assert(fr.x() >= 0.0f and fr.x() < 1.0f);
assert(fr.y() >= 0.0f and fr.y() < 1.0f);
//see:
//http://stackoverflow.com/questions/12367071/how-do-i-initialize-the-t-variables-in-a-fast-voxel-traversal-algorithm-for-ray#12370474
vec2i step(sgn(v.x()), sgn(v.y()));
const vec2i step(sgn(v.x()), sgn(v.y()));
vec2f max;
if (step.x() > 0)
max.x() = delta.x() * (1.0f - fr.x());
else if (step.x() < 0)
max.x() = delta.x() * fr.x();
else
max.x() = FLT_MAX;
if (step.y() > 0)
max.y() = delta.y() * (1.0f - fr.y());
else if (step.y() < 0)
max.y() = delta.y() * fr.y();
else
max.y() = FLT_MAX;
vec2us curr_tile = pixel_to_world_tile(parWorld, u);
const vec2us last_tile = pixel_to_world_tile(parWorld, parTo);
while (parFunc(curr_tile) and last_tile != curr_tile) {
if (max.x() < max.y()) {
assert(std::max(static_cast<uint16_t>(curr_tile.x() + step.x()), last_tile.x()) - std::min(static_cast<uint16_t>(curr_tile.x() + step.x()), last_tile.x()) < std::max(curr_tile.x(), last_tile.x()) - std::min(curr_tile.x(), last_tile.x()));
assert(step.x());
assert(
std::max(static_cast<uint16_t>(curr_tile.x() + step.x()), last_tile.x()) -
std::min(static_cast<uint16_t>(curr_tile.x() + step.x()), last_tile.x()) <
std::max(curr_tile.x(), last_tile.x()) -
std::min(curr_tile.x(), last_tile.x())
);
max.x() += delta.x();
curr_tile.x() = static_cast<uint16_t>(curr_tile.x() + step.x());
}
else {
assert(std::max(static_cast<uint16_t>(curr_tile.y() + step.y()), last_tile.y()) - std::min(static_cast<uint16_t>(curr_tile.y() + step.y()), last_tile.y()) < std::max(curr_tile.y(), last_tile.y()) - std::min(curr_tile.y(), last_tile.y()));
assert(step.y());
assert(
std::max(static_cast<uint16_t>(curr_tile.y() + step.y()), last_tile.y()) -
std::min(static_cast<uint16_t>(curr_tile.y() + step.y()), last_tile.y()) <
std::max(curr_tile.y(), last_tile.y()) -
std::min(curr_tile.y(), last_tile.y())
);
max.y() += delta.y();
curr_tile.y() = static_cast<uint16_t>(curr_tile.y() + step.y());
}