Cement FOV and camera placement changes

Source/PluginProcessor.h

@@ -103,7 +103,7 @@ public:
         perspectiveEffect,
         std::vector<osci::EffectParameter*>{
             new osci::EffectParameter("Perspective", "Controls the strength of the 3D perspective projection.", "perspectiveStrength", VERSION_HINT, 1.0, 0.0, 1.0),
-            new osci::EffectParameter("FOV", "Controls the focal length of the 3D perspective effect. A higher focal length makes the image look more flat, and a lower focal length makes the image look more 3D.", "perspectiveFocalLength", VERSION_HINT, 70.0, 1.0, 150.0),
+            new osci::EffectParameter("FOV", "Controls the camera's field of view in degrees. A lower field of view makes the image look more flat, and a higher field of view makes the image look more 3D.", "perspectiveFov", VERSION_HINT, 55.0, 5.0, 140.0),
         });
 
     osci::BooleanParameter* midiEnabled = new osci::BooleanParameter("MIDI Enabled", "midiEnabled", VERSION_HINT, false, "Enable MIDI input for the synth. If disabled, the synth will play a constant tone, as controlled by the frequency slider.");

Source/audio/PerspectiveEffect.h

@@ -6,18 +6,14 @@ class PerspectiveEffect : public osci::EffectApplication {
 public:
 	osci::Point apply(int index, osci::Point input, const std::vector<std::atomic<double>>& values, double sampleRate) override {
 		auto effectScale = values[0].load();
-		//auto focalLength = juce::jmax(values[1].load(), 0.001);
-		double fovDegrees = juce::jmax(values[1].load(), 0.1);
+		// Far plane clipping happens at about 1.2 deg for 100 far plane dist
+		double fovDegrees = juce::jlimit(1.5, 179.0, values[1].load());
 		double fov = juce::degreesToRadians(fovDegrees);
-		double focalLength = 1.0 / std::tan(0.5 * fov);
 
-
-		// Place such that view frustum is tangent to unit sphere
-		//Vec3 origin = Vec3(0, 0, -std::sqrt(1 + focalLength * focalLength));
-		// TODO
+		// Place camera such that field of view is tangent to unit sphere
 		Vec3 origin = Vec3(0, 0, -1.0f / std::sin(0.5f * (float)fov));
 		camera.setPosition(origin);
-		camera.setFocalLength(focalLength);
+		camera.setFov(fov);
 		Vec3 vec = Vec3(input.x, input.y, input.z);
 
 		Vec3 projected = camera.project(vec);
@@ -30,6 +26,6 @@ public:
 	}
 
 private:
-
+	
 	Camera camera;
 };

Source/obj/Camera.cpp

@@ -1,6 +1,6 @@
 #include "Camera.h"
 
-Camera::Camera() : frustum(1, 1, 0.1, 100) {
+Camera::Camera() : frustum(1, 1, 0.001, 100) {
     viewMatrix = mathter::Identity();
 }
 
@@ -18,8 +18,8 @@ Vec3 Camera::toWorldSpace(Vec3& point) {
     return mathter::Inverse(viewMatrix) * point;
 }
 
-void Camera::setFocalLength(double focalLength) {
-    frustum.setCameraInternals(focalLength, frustum.ratio, frustum.nearDistance, frustum.farDistance);
+void Camera::setFov(double fov) {
+    frustum.setCameraInternals(fov, frustum.ratio, frustum.nearDistance, frustum.farDistance);
 }
 
 Vec3 Camera::project(Vec3& pWorld) {
@@ -27,10 +27,10 @@ Vec3 Camera::project(Vec3& pWorld) {
 
     frustum.clipToFrustum(p);
 
-    double start = p.x * frustum.focalLength / p.z;
-    double end = p.y * frustum.focalLength / p.z;
+    float x = p.x * frustum.focalLength / p.z;
+    float y = p.y * frustum.focalLength / p.z;
 
-    return Vec3(start, end, 0);
+    return Vec3(x, y, 0);
 }
 
 Frustum Camera::getFrustum() {

Source/obj/Camera.h

@@ -12,7 +12,7 @@ public:
 	void setPosition(Vec3& position);
 	Vec3 toCameraSpace(Vec3& point);
 	Vec3 toWorldSpace(Vec3& point);
-	void setFocalLength(double focalLength);
+	void setFov(double fov);
 	Vec3 project(Vec3& p);
 	Frustum getFrustum();
 private:

Source/obj/Frustum.cpp

@@ -2,16 +2,16 @@
 
 #include "Frustum.h"
 
-void Frustum::setCameraInternals(float focalLength, float ratio, float nearDistance, float farDistance) {
+void Frustum::setCameraInternals(float fov, float ratio, float nearDistance, float farDistance) {
 	// store the information
-	this->focalLength = focalLength;
+	this->fov = fov;
 	this->ratio = ratio;
 	this->nearDistance = nearDistance;
 	this->farDistance = farDistance;
 
 	// compute width and height of the near section
-	float fov = 2 * std::atan(1 / focalLength);
-	tang = (float) std::tan(fov * 0.5);
+	tang = std::tan(fov * 0.5f);
+	focalLength = 1.0f / tang;
 	height = nearDistance * tang;
 	width = height * ratio;
 }

Source/obj/Frustum.h

@@ -9,16 +9,13 @@ using Vec3 = mathter::Vector<float, 3, false>;
 
 class Frustum {
 public:
-	float ratio, nearDistance, farDistance, width, height, tang, focalLength;
+	float ratio, nearDistance, farDistance, width, height, tang, fov, focalLength;
 
-	Frustum(float focalLength, float ratio, float nearDistance, float farDistance) {
-        setCameraInternals(focalLength, ratio, nearDistance, farDistance);
+	Frustum(float fov, float ratio, float nearDistance, float farDistance) {
+        setCameraInternals(fov, ratio, nearDistance, farDistance);
     }
 	~Frustum() {};
 
-	void setCameraInternals(float focalLength, float ratio, float nearD, float farD);
+	void setCameraInternals(float fov, float ratio, float nearD, float farD);
 	void clipToFrustum(Vec3 &p);
-	float getFocalLength() {
-        return focalLength;
-    }
 };