From ada904a413214d242ab586ba634bc5ed6590ccef Mon Sep 17 00:00:00 2001
From: Robert Chisholm <robadob@robadob.org>
Date: Sat, 19 Oct 2024 17:38:36 +0100
Subject: [PATCH] Add support for an initial camera roll angle

---
 include/flamegpu/visualiser/config/ModelConfig.h | 4 ++++
 src/flamegpu/visualiser/Visualiser.cpp           | 2 +-
 src/flamegpu/visualiser/camera/NoClipCamera.cpp  | 5 ++---
 src/flamegpu/visualiser/camera/NoClipCamera.h    | 3 ++-
 src/flamegpu/visualiser/config/ModelConfig.cpp   | 2 ++
 5 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/include/flamegpu/visualiser/config/ModelConfig.h b/include/flamegpu/visualiser/config/ModelConfig.h
index 7446bae..d273ce3 100644
--- a/include/flamegpu/visualiser/config/ModelConfig.h
+++ b/include/flamegpu/visualiser/config/ModelConfig.h
@@ -90,6 +90,10 @@ struct ModelConfig {
      * @note Defaults to (0,0,0)
      */
     float cameraTarget[3];
+    /**
+     * The initial camera roll angle in radians
+     */
+    float cameraRoll;
     /**
      * The movement speed of the camera in units per millisecond, and the shift key multiplier
      * When shift is pressed the movement speed is multiplied by this value
diff --git a/src/flamegpu/visualiser/Visualiser.cpp b/src/flamegpu/visualiser/Visualiser.cpp
index 74e6678..016e520 100644
--- a/src/flamegpu/visualiser/Visualiser.cpp
+++ b/src/flamegpu/visualiser/Visualiser.cpp
@@ -125,7 +125,7 @@ void addLine(std::shared_ptr<Draw> &lines, const std::shared_ptr<LineConfig> &li
 }
 Visualiser::Visualiser(const ModelConfig& modelcfg)
     : hud(std::make_shared<HUD>(modelcfg.windowDimensions[0], modelcfg.windowDimensions[1]))
-    , camera(std::make_shared<NoClipCamera>(*reinterpret_cast<const glm::vec3*>(&modelcfg.cameraLocation[0]), *reinterpret_cast<const glm::vec3*>(&modelcfg.cameraTarget[0])))
+    , camera(std::make_shared<NoClipCamera>(*reinterpret_cast<const glm::vec3*>(&modelcfg.cameraLocation[0]), *reinterpret_cast<const glm::vec3*>(&modelcfg.cameraTarget[0]), modelcfg.cameraRoll))
     , isInitialised(false)
     , continueRender(false)
     , buffersAllocated(false)
diff --git a/src/flamegpu/visualiser/camera/NoClipCamera.cpp b/src/flamegpu/visualiser/camera/NoClipCamera.cpp
index 7fc227a..7cde22d 100644
--- a/src/flamegpu/visualiser/camera/NoClipCamera.cpp
+++ b/src/flamegpu/visualiser/camera/NoClipCamera.cpp
@@ -16,7 +16,7 @@ NoClipCamera::NoClipCamera(const glm::vec3 &eye)
     : NoClipCamera(eye, glm::vec3(0, 0, 0)) {}
 // Initialiser list written to remove any references to member variables
 // Because member variables are initialised via initaliser lists in the order they are declared in the class declaration (rather than the order of the initialiser list)
-NoClipCamera::NoClipCamera(const glm::vec3 &eye, const glm::vec3 &target)
+NoClipCamera::NoClipCamera(const glm::vec3 &eye, const glm::vec3 &target, const float _roll)
     : Camera(eye)
     , pureUp(0.0f, 1.0f, 0.0f)
     , look(normalize(target - eye))
@@ -27,8 +27,7 @@ NoClipCamera::NoClipCamera(const glm::vec3 &eye, const glm::vec3 &target)
     // this->look = target - eye;                        // Look is the direction from eye to target
     // this->right = cross(look, pureUp);                // Right is perpendicular to look and pureUp
     // this->up = cross(right, look);                    // Up is perpendicular to right and look
-
-    this->updateViews();
+    this->roll(_roll);
 }
 NoClipCamera::~NoClipCamera() {
 }
diff --git a/src/flamegpu/visualiser/camera/NoClipCamera.h b/src/flamegpu/visualiser/camera/NoClipCamera.h
index e2b540f..515215e 100644
--- a/src/flamegpu/visualiser/camera/NoClipCamera.h
+++ b/src/flamegpu/visualiser/camera/NoClipCamera.h
@@ -22,8 +22,9 @@ class NoClipCamera : public Camera {
     * Initialises the camera located at eye directed at target
     * @param eye The coordinates the camera is located
     * @param target The coordinates the camera is directed towards
+    * @param _roll The camera roll in radians
     */
-    NoClipCamera(const glm::vec3 &eye, const glm::vec3 &target);
+    NoClipCamera(const glm::vec3 &eye, const glm::vec3 &target, float _roll = 0);
     /**
      * Default destructor
      */
diff --git a/src/flamegpu/visualiser/config/ModelConfig.cpp b/src/flamegpu/visualiser/config/ModelConfig.cpp
index 78800b3..a28d5c2 100644
--- a/src/flamegpu/visualiser/config/ModelConfig.cpp
+++ b/src/flamegpu/visualiser/config/ModelConfig.cpp
@@ -19,6 +19,7 @@ ModelConfig::ModelConfig(const char* _windowTitle)
     , fpsColor{1, 1, 1}
     , cameraLocation{1.5f, 1.5f, 1.5f}
     , cameraTarget{0, 0, 0}
+    , cameraRoll(0)
     , cameraSpeed{0.05f, 5}
     , nearFarClip{0.05f, 5000}
     , stepVisible(true)
@@ -39,6 +40,7 @@ ModelConfig &ModelConfig::operator=(const ModelConfig &other) {
     memcpy(fpsColor, other.fpsColor, sizeof(fpsColor));
     memcpy(cameraLocation, other.cameraLocation, sizeof(cameraLocation));
     memcpy(cameraTarget, other.cameraTarget, sizeof(cameraTarget));
+    cameraRoll = other.cameraRoll;
     memcpy(cameraSpeed, other.cameraSpeed, sizeof(cameraSpeed));
     memcpy(nearFarClip, other.nearFarClip, sizeof(nearFarClip));
     stepVisible = other.stepVisible;