diff options
Diffstat (limited to 'src/tile-atlas.cpp')
| -rw-r--r-- | src/tile-atlas.cpp | 25 |
1 files changed, 16 insertions, 9 deletions
diff --git a/src/tile-atlas.cpp b/src/tile-atlas.cpp index 1867189f..9cfb7998 100644 --- a/src/tile-atlas.cpp +++ b/src/tile-atlas.cpp @@ -34,20 +34,27 @@ std::array<Vector2, 4> tile_atlas::texcoords_for_id(size_t i) const return texcoords_[i]; } -auto tile_atlas::make_texcoords(Vector2ui pixel_size, Vector2ub tile_count, size_t i) -> texcoords +auto tile_atlas::texcoords_at(Vector2ui pos, Vector2ui size, Vector2ui image_size) -> texcoords { - const auto sz = pixel_size/Vector2ui{tile_count}; - const Vector2ui id = { uint32_t(i % tile_count[0]), uint32_t(i / tile_count[0]) }; - const Vector2 p0(id * sz), p1(sz); - const auto x0 = p0.x()+.5f, x1 = p1.x()-1, y0 = p0.y()+.5f, y1 = p1.y()-1; + const auto x0 = (float)pos.x()+.5f, x1 = x0 + (float)size.x()-1, + y0 = (float)pos.y()+.5f, y1 = y0 + (float)size.y()-1; + const auto W = image_size.x(), H = image_size.y(); return {{ - { (x0+x1) / pixel_size[0], 1 - (y0+y1) / pixel_size[1] }, // bottom right - { (x0+x1) / pixel_size[0], 1 - y0 / pixel_size[1] }, // top right - { x0 / pixel_size[0], 1 - (y0+y1) / pixel_size[1] }, // bottom left - { x0 / pixel_size[0], 1 - y0 / pixel_size[1] }, // top left + { x1 / W, 1 - y1 / H }, // bottom right + { x1 / W, 1 - y0 / H }, // top right + { x0 / W, 1 - y1 / H }, // bottom left + { x0 / W, 1 - y0 / H }, // top left }}; } +auto tile_atlas::make_texcoords(Vector2ui pixel_size, Vector2ub tile_count, size_t i) -> texcoords +{ + const auto sz = pixel_size/Vector2ui{tile_count}; + const auto id = Vector2ui{ uint32_t(i % tile_count[0]), uint32_t(i / tile_count[0]) }; + const auto p0 = id * sz; + return texcoords_at(p0, sz, pixel_size); +} + auto tile_atlas::make_texcoords_array(Vector2ui pixel_size, Vector2ub tile_count) -> std::unique_ptr<const texcoords[]> { const size_t N = Vector2ui{tile_count}.product(); |