From daed922f23daa8a8e2659d8aea7864cccd5e08c7 Mon Sep 17 00:00:00 2001
From: Dan Goodliffe <dan@randomdan.homeip.net>
Date: Mon, 11 Dec 2023 20:11:23 +0000
Subject: Integer camera

---
 gfx/gl/camera.cpp | 36 ++++++++++++++++++------------------
 1 file changed, 18 insertions(+), 18 deletions(-)

(limited to 'gfx/gl/camera.cpp')

diff --git a/gfx/gl/camera.cpp b/gfx/gl/camera.cpp
index 15f76c4..a0d76ab 100644
--- a/gfx/gl/camera.cpp
+++ b/gfx/gl/camera.cpp
@@ -1,14 +1,14 @@
 #include "camera.h"
 #include <collections.h>
-#include <glm/gtx/intersect.hpp> // IWYU pragma: keep
-#include <glm/gtx/transform.hpp> // IWYU pragma: keep
-#include <math.h>
+#include <glm/gtx/transform.hpp>
 #include <maths.h>
 #include <ray.h>
 
-Camera::Camera(Position3D pos, Angle fov, Angle aspect, Distance zNear, Distance zFar) :
+Camera::Camera(GlobalPosition3D pos, Angle fov, Angle aspect, GlobalDistance zNear, GlobalDistance zFar) :
 	position {pos}, forward {::north}, up {::up}, near {zNear}, far {zFar},
-	projection {glm::perspective(fov, aspect, zNear, zFar)}, viewProjection {}, inverseViewProjection {}
+	projection {
+			glm::perspective(fov, aspect, static_cast<RelativeDistance>(zNear), static_cast<RelativeDistance>(zFar))},
+	viewProjection {}, inverseViewProjection {}
 {
 	updateView();
 }
@@ -25,7 +25,7 @@ void
 Camera::updateView()
 {
 	viewProjection = projection * glm::lookAt(origin, forward, up);
-	inverseViewProjection = glm::inverse(projection * glm::lookAt(position, position + forward, up));
+	inverseViewProjection = glm::inverse(viewProjection);
 }
 
 Direction3D
@@ -35,21 +35,21 @@ Camera::upFromForward(const Direction3D & forward)
 	return glm::cross(forward, right);
 }
 
-std::array<glm::vec4, 4>
-Camera::extentsAtDist(const float dist) const
+std::array<GlobalPosition4D, 4>
+Camera::extentsAtDist(const GlobalDistance dist) const
 {
-	const auto clampToSeaFloor = [this, dist](const Position3D & target) {
-		if (target.z < -1.5F) {
-			const auto vec = glm::normalize(target - position);
-			constexpr Position3D seafloor {0, 0, -1.5F};
-			float outdist {};
-			if (glm::intersectRayPlane(position, vec, seafloor, ::up, outdist)) {
-				return (vec * outdist + position) ^ outdist;
-			}
+	const auto clampToSeaFloor = [this, dist](GlobalPosition3D target) -> GlobalPosition4D {
+		target += position;
+		if (target.z < -1500) {
+			const auto diff = (target - position);
+			const auto something = (-1500 - position.z) / diff.z;
+			return {position + diff * something, dist};
 		}
-		return target ^ dist;
+		return {target, dist};
 	};
-	const auto depth = -(2.F * (dist - near) * far) / (dist * (near - far)) - 1.F;
+	const auto depth = -(2.F * (static_cast<float>(dist - near)) * static_cast<float>(far))
+					/ (static_cast<float>(dist) * (static_cast<float>(near - far)))
+			- 1.F;
 	static constexpr const std::array extents {-1.F, 1.F};
 	static constexpr const auto cartesianExtents = extents * extents;
 	return cartesianExtents * [&depth, this, &clampToSeaFloor](const auto & extent) {
-- 
cgit v1.2.3