From be3ae18a21edd71d120caca6b4b5c548f52c7998 Mon Sep 17 00:00:00 2001
From: Philip Abernethy <chais.z3r0@gmail.com>
Date: Wed, 12 Aug 2015 17:48:34 +0200
Subject: [PATCH] Fixed the transformations

---
 lib/geometry/sphere.cpp | 10 +++++-----
 main.cpp                | 17 ++++++++++-------
 test.cpp                |  6 ++++--
 3 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/lib/geometry/sphere.cpp b/lib/geometry/sphere.cpp
index 1482eab..4d9e2a3 100644
--- a/lib/geometry/sphere.cpp
+++ b/lib/geometry/sphere.cpp
@@ -19,7 +19,7 @@ ray sphere::intersect(ray r) {
 	mat4 m = this->getTransforms();
 	mat4 im = this->getInvTransforms();
 	ray tr = ray(im*r.getOrigin(), transform(im, r.getDirection()));
-	vec3 c = this->getPosition()-tr.getOrigin();
+	vec3 c = -tr.getOrigin();
 	double a = std::max(0.0, dot(tr.getDirection(), c));
 	double b = std::sqrt(std::pow(length(c), 2)-std::pow(a, 2));
 	if (b < this->radius-1E-12) {
@@ -29,11 +29,11 @@ ray sphere::intersect(ray r) {
 			x = tr.getOrigin()+tr.getDirection()*(a-d);
 		else
 			x = tr.getOrigin()+tr.getDirection()*(a+d);
-		vec3 dir = x-this->getPosition();
+		vec3 dir = x;
+		double local_len = length(x);
+		vec3 col = this->getColor(x[0]/local_len, x[1]/local_len);
 		x = m*x;
 		dir = transform(transpose(im), dir);
-		double local_len = length(x-this->getPosition());
-		vec3 col = this->getColor(x[0]/local_len, x[1]/local_len);
 		return ray(x, dir, col);
 	}
 	throw geometry_exception("No intersection");
@@ -42,7 +42,7 @@ ray sphere::intersect(ray r) {
 bool sphere::getShadow(vec3 origin, vec3 direction) {
 	mat4 im = this->getInvTransforms();
 	ray tr = ray(im*origin, transform(im, direction));
-	vec3 c = this->getPosition()-tr.getOrigin();
+	vec3 c = -tr.getOrigin();
 	double a = dot(tr.getDirection(), c);
 	double b = std::sqrt(std::pow(length(c), 2)-std::pow(a, 2));
 	return (a > 0 && b < this->radius);
diff --git a/main.cpp b/main.cpp
index 16e0bb5..4cf86d3 100644
--- a/main.cpp
+++ b/main.cpp
@@ -17,13 +17,16 @@ int main() {
 	solid_material *red_lack = new solid_material(vec3{1, 0, 0}, lack, 0, 0, 0);
 	std::vector<shape*> scene;
 	scene.push_back(new sphere(1.0, red_lack));
-	scene[0]->translate(vec3{0, -2, -4});
-	scene[0]->rotateZ(90);
-	//scene[0]->scale(sf);
-	/*scene.push_back(new sphere(1.0, red_lack));
-	scene[1]->translate(vec3{0, -2, -1});
-	double sf[] = {100, 0.1, 100};
-	scene[1]->scale(sf);*/
+	scene[0]->translate(vec3{0, -1, -7});
+	scene[0]->rotateZ(30);
+	double sf[] = {2, 1, 1};
+	scene[0]->scale(sf);
+	scene.push_back(new sphere(1.0, red_lack));
+	scene[1]->translate(vec3{0, -4, -1});
+	sf[0] = 100;
+	sf[1] = 0.1;
+	sf[2] = 100;
+	scene[1]->scale(sf);
 	whitted_rt rt = whitted_rt(bgcolor, cam, lights, scene);
 	rt.render();
 	png::image<png::rgb_pixel> img(1024, 768);
diff --git a/test.cpp b/test.cpp
index 4daffd1..bb05c30 100644
--- a/test.cpp
+++ b/test.cpp
@@ -81,10 +81,12 @@ int main(int argc, char *argv[]) {
 	sphere1.rotateZ(90);
 	cout << "Transforms: " << sphere1.getTransforms() << endl;
 	cout << "Inv. Transforms: " << sphere1.getInvTransforms() << endl;
-	cout << "Scale" << endl;
+	/*cout << "Scale" << endl;
 	sf[0] = 2;
 	sf[1] = 1;
 	sphere1.scale(sf);
 	cout << "Transforms: " << sphere1.getTransforms() << endl;
-	cout << "Inv. Transforms: " << sphere1.getInvTransforms() << endl;
+	cout << "Inv. Transforms: " << sphere1.getInvTransforms() << endl;*/
+	cout << "M*[0 0 0]'=" << sphere1.getInvTransforms()*vec3{0, 0, 0} << endl;
+	cout << "M*[0 -0.2 -1]'=" << transform(sphere1.getInvTransforms(), normalise(vec3{0, -0.2, -1})) << endl;
 }
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