/* * Copyright (C) 2023 Christopher J. Howard * * This file is part of Antkeeper source code. * * Antkeeper source code is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * Antkeeper source code is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with Antkeeper source code. If not, see . */ #include #include #include namespace scene { geom::ray camera::pick(const math::fvec2& ndc) const { const auto near = m_inv_view_projection * math::fvec4{ndc[0], ndc[1], 1.0f, 1.0f}; const auto far = m_inv_view_projection * math::fvec4{ndc[0], ndc[1], 0.0f, 1.0f}; const auto origin = math::fvec3{near[0], near[1], near[2]} / near[3]; const auto direction = math::normalize(math::fvec3{far[0], far[1], far[2]} / far[3] - origin); return {origin, direction}; } math::fvec3 camera::project(const math::fvec3& object, const math::fvec4& viewport) const { math::fvec4 result = m_view_projection * math::fvec4{object[0], object[1], object[2], 1.0f}; result[0] = (result[0] / result[3]) * 0.5f + 0.5f; result[1] = (result[1] / result[3]) * 0.5f + 0.5f; result[2] = (result[2] / result[3]) * 0.5f + 0.5f; result[0] = result[0] * viewport[2] + viewport[0]; result[1] = result[1] * viewport[3] + viewport[1]; return math::fvec3(result); } math::fvec3 camera::unproject(const math::fvec3& window, const math::fvec4& viewport) const { math::fvec4 result; result[0] = ((window[0] - viewport[0]) / viewport[2]) * 2.0f - 1.0f; result[1] = ((window[1] - viewport[1]) / viewport[3]) * 2.0f - 1.0f; //result[2] = window[2] * 2.0f - 1.0f; z: [-1, 1] //result[2] = window[2]; // z: [0, 1] result[2] = 1.0f - window[2]; // z: [1, 0] result[3] = 1.0f; result = m_inv_view_projection * result; return math::fvec3(result) * (1.0f / result[3]); } void camera::set_perspective(float vertical_fov, float aspect_ratio, float clip_near, float clip_far) { // Set projection mode to perspective m_orthographic = false; // Update perspective projection parameters m_vertical_fov = vertical_fov; m_aspect_ratio = aspect_ratio; m_clip_near = clip_near; m_clip_far = clip_far; // Recalculate projection matrix and its inverse std::tie(m_projection, m_inv_projection) = math::perspective_half_z_inv(m_vertical_fov, m_aspect_ratio, m_clip_far, m_clip_near); // Recalculate view-projection matrix m_view_projection = m_projection * m_view; m_inv_view_projection = m_inv_view * m_inv_projection; // Recalculate view frustum update_frustum(); } void camera::set_vertical_fov(float vertical_fov) { if (!m_orthographic) { set_perspective(vertical_fov, m_aspect_ratio, m_clip_near, m_clip_far); } } void camera::set_orthographic(float clip_left, float clip_right, float clip_bottom, float clip_top, float clip_near, float clip_far) { // Set projection mode to orthographic m_orthographic = true; // Update signed distances to clipping planes m_clip_left = clip_left; m_clip_right = clip_right; m_clip_bottom = clip_bottom; m_clip_top = clip_top; m_clip_near = clip_near; m_clip_far = clip_far; // Recalculate projection matrix and its inverse std::tie(m_projection, m_inv_projection) = math::ortho_half_z_inv(m_clip_left, m_clip_right, m_clip_bottom, m_clip_top, m_clip_far, m_clip_near); // Update view-projection matrix and its inverse m_view_projection = m_projection * m_view; m_inv_view_projection = m_inv_view * m_inv_projection; // Update view frustum update_frustum(); } void camera::set_exposure_value(float ev100) { m_exposure_value = ev100; // m_exposure_normalization = 1.0f / (std::exp2(m_exposure_value) * 1.2f); m_exposure_normalization = 1.0f / (std::exp2(m_exposure_value)); } void camera::transformed() { // Update basis vectors m_forward = get_rotation() * math::fvec3{0.0f, 0.0f, -1.0f}; m_up = get_rotation() * math::fvec3{0.0f, 1.0f, 0.0f}; // Recalculate view matrix and its inverse std::tie(m_view, m_inv_view) = math::look_at_rh_inv(get_translation(), get_translation() + m_forward, m_up); // Update view-projection matrix and its inverse m_view_projection = m_projection * m_view; m_inv_view_projection = m_inv_view * m_inv_projection; // Update view frustum update_frustum(); } void camera::update_frustum() { // Recalculate view frustum m_view_frustum.extract(m_view_projection); // Reverse half z clip-space coordinates of a cube constexpr math::fvec4 clip_space_cube[8] = { {-1, -1, 1, 1}, // NBL { 1, -1, 1, 1}, // NBR {-1, 1, 1, 1}, // NTL { 1, 1, 1, 1}, // NTR {-1, -1, 0, 1}, // FBL { 1, -1, 0, 1}, // FBR {-1, 1, 0, 1}, // FTL { 1, 1, 0, 1} // FTR }; // Update bounds m_bounds = {math::fvec3::infinity(), -math::fvec3::infinity()}; for (std::size_t i = 0; i < 8; ++i) { const math::fvec4 frustum_corner = m_inv_view_projection * clip_space_cube[i]; m_bounds.extend(math::fvec3(frustum_corner) / frustum_corner[3]); } } } // namespace scene