Add a super special Camera from a well known constructor. Can take picture up to Infinite TeraPixel!

source/camera.cpp

@@ -0,0 +1,74 @@
+/*
+ *  DoRayMe - a quick and dirty Raytracer
+ *  Camera implementation
+ *
+ *  Created by Manoël Trapier
+ *  Copyright (c) 2020 986-Studio.
+ *
+ */
+#include <matrix.h>
+#include <stdint.h>
+#include <math.h>
+#include <ray.h>
+#include <camera.h>
+
+Camera::Camera(uint32_t hsize, uint32_t vsize, double fov) : verticalSize(vsize), horizontalSize(hsize), fieldOfView(fov)
+{
+    double aspectRatio = (double)hsize / (double)vsize;
+    double halfView = tan(fov / 2.0);
+
+    if (aspectRatio >= 1)
+    {
+        this->halfWidth = halfView;
+        this->halfHeight = halfView / aspectRatio;
+    }
+    else
+    {
+        this->halfWidth = halfView * aspectRatio;
+        this->halfHeight = halfView;
+    }
+
+    this->pixelSize = (this->halfWidth * 2) / this->horizontalSize;
+
+    this->setTransform(Matrix4().identity());
+
+}
+
+void Camera::setTransform(Matrix transform)
+{
+    this->transformMatrix = transform;
+    this->inverseTransform = transform.inverse();
+}
+
+Ray Camera::rayForPixel(uint32_t pixelX, uint32_t pixelY)
+{
+    double xOffset = ((double)pixelX + 0.5) * this->pixelSize;
+    double yOffset = ((double)pixelY + 0.5) * this->pixelSize;
+
+    double worldX = this->halfWidth - xOffset;
+    double worldY = this->halfHeight - yOffset;
+
+    Tuple pixel = this->inverseTransform * Point(worldX, worldY, -1);
+    Tuple origin = this->inverseTransform * Point(0, 0, 0);
+    Tuple direction = (pixel - origin).normalise();
+
+    return Ray(origin, direction);
+}
+
+Canvas Camera::render(World world)
+{
+    uint32_t x, y;
+    Canvas image = Canvas(this->horizontalSize, this->verticalSize);
+
+    for(y = 0; y < this->verticalSize; y++)
+    {
+        for(x = 0; x < this->horizontalSize; x++)
+        {
+            Ray r = this->rayForPixel(x, y);
+            Tuple colour = world.colourAt(r);
+            image.putPixel(x, y, colour);
+        }
+    }
+
+    return image;
+}

source/include/camera.h

@@ -0,0 +1,38 @@
+/*
+ *  DoRayMe - a quick and dirty Raytracer
+ *  Camera header
+ *
+ *  Created by Manoël Trapier
+ *  Copyright (c) 2020 986-Studio.
+ *
+ */
+#ifndef DORAYME_CAMERA_H
+#define DORAYME_CAMERA_H
+
+#include <matrix.h>
+#include <stdint.h>
+#include <ray.h>
+#include <canvas.h>
+#include <world.h>
+
+class Camera
+{
+private:
+    double halfWidth;
+    double halfHeight;
+public:
+    uint32_t verticalSize;
+    uint32_t horizontalSize;
+    double fieldOfView;
+    double pixelSize;
+    Matrix transformMatrix;
+    Matrix inverseTransform;
+
+public:
+    Camera(uint32_t hsize, uint32_t vsize, double fov);
+    void setTransform(Matrix transform);
+    Ray rayForPixel(uint32_t pixelX, uint32_t pixelY);
+    Canvas render(World w);
+};
+
+#endif /* DORAYME_CAMERA_H */

tests/CMakeLists.txt

@@ -4,7 +4,7 @@ set(THREADS_PREFER_PTHREAD_FLAG ON)
 find_package(Threads REQUIRED)
 
 set(TESTS_SRC tuple_test.cpp colour_test.cpp canvas_test.cpp matrix_test.cpp transformation_test.cpp ray_test.cpp
-        intersect_test.cpp sphere_test.cpp light_test.cpp material_test.cpp world_test.cpp)
+        intersect_test.cpp sphere_test.cpp light_test.cpp material_test.cpp world_test.cpp camera_test.cpp)
 
 add_executable(testMyRays)
 target_include_directories(testMyRays PUBLIC ${gtest_SOURCE_DIR}/include ${gtest_SOURCE_DIR})
@@ -28,5 +28,11 @@ target_include_directories(ch6_test PUBLIC ../source/include)
 target_sources(ch6_test PRIVATE ch6_test.cpp)
 target_link_libraries(ch6_test rayonnement)
 
+add_executable(ch7_test)
+target_include_directories(ch6_test PUBLIC ../source/include)
+target_sources(ch7_test PRIVATE ch7_test.cpp)
+target_link_libraries(ch7_test rayonnement)
+
 add_test(NAME Chapter05_Test COMMAND $<TARGET_FILE:ch5_test>)
 add_test(NAME Chapter06_Test COMMAND $<TARGET_FILE:ch6_test>)
+add_test(NAME Chapter07_Test COMMAND $<TARGET_FILE:ch7_test>)

tests/camera_test.cpp

@@ -0,0 +1,111 @@
+/*
+ *  DoRayMe - a quick and dirty Raytracer
+ *  Camera unit tests
+ *
+ *  Created by Manoël Trapier
+ *  Copyright (c) 2020 986-Studio.
+ *
+ */
+#include <camera.h>
+#include <math.h>
+#include <math_helper.h>
+#include <matrix.h>
+#include <tuple.h>
+#include <ray.h>
+#include <world.h>
+#include <canvas.h>
+#include <colour.h>
+#include <worldbuilder.h>
+#include <transformation.h>
+#include <stdint.h>
+#include <gtest/gtest.h>
+
+TEST(CameraTest, Constructing_a_camera)
+{
+    uint32_t hsize = 160;
+    uint32_t vsize = 120;
+    double field_of_view = M_PI / 2;
+
+    Camera c = Camera(hsize, vsize, field_of_view);
+
+    ASSERT_EQ(c.horizontalSize, 160);
+    ASSERT_EQ(c.verticalSize, 120);
+    ASSERT_TRUE(double_equal(c.fieldOfView, M_PI / 2));
+    ASSERT_EQ(c.transformMatrix, Matrix4().identity());
+}
+
+TEST(CameraTest, Pixel_size_for_a_horizontal_canvas)
+{
+    Camera c = Camera(200, 125, M_PI / 2);
+
+    ASSERT_TRUE(double_equal(c.pixelSize, 0.01));
+}
+
+TEST(CameraTest, Pixel_size_for_a_vertical_canvas)
+{
+    Camera c = Camera(125, 200, M_PI / 2);
+
+    ASSERT_TRUE(double_equal(c.pixelSize, 0.01));
+}
+
+TEST(CameraTest, Constructing_a_ray_through_the_center_of_the_canvas)
+{
+    Camera c = Camera(201, 101, M_PI / 2);
+    Ray r = c.rayForPixel(100, 50);
+
+    ASSERT_EQ(r.origin, Point(0, 0, 0));
+    ASSERT_EQ(r.direction, Vector(0, 0, -1));
+}
+
+TEST(CameraTest, Constructing_a_ray_through_a_corner_of_the_canvas)
+{
+    Camera c = Camera(201, 101, M_PI / 2);
+    Ray r = c.rayForPixel(0, 0);
+
+    ASSERT_EQ(r.origin, Point(0, 0, 0));
+
+    /* Temporary lower the precision */
+    set_equal_precision(0.00001);
+
+    ASSERT_EQ(r.direction, Vector(0.66519, 0.33259, -0.66851));
+
+    set_equal_precision(FLT_EPSILON);
+}
+
+TEST(CameraTest, Constructing_a_ray_when_the_camera_is_transformed)
+{
+    Camera c = Camera(201, 101, M_PI / 2);
+    c.setTransform(rotationY(M_PI / 4) * translation(0, -2, 5));
+    Ray r = c.rayForPixel(100, 50);
+
+    ASSERT_EQ(r.origin, Point(0, 2, -5));
+    ASSERT_EQ(r.direction, Vector(sqrt(2)/2, 0, -sqrt(2)/2));
+}
+
+TEST(CameraTest, Rendering_a_world_with_a_camera)
+{
+    World w = DefaultWorld();
+    Camera c = Camera(11, 11, M_PI / 2);
+
+    Tuple from = Point(0, 0, -5);
+    Tuple to = Point(0, 0, 0);
+    Tuple up = Vector(0, 1, 0);
+
+    c.setTransform(viewTransform(from, to, up));
+
+    Canvas image = c.render(w);
+
+    /* Temporary lower the precision */
+    /* We need to lower a lot as Canvas is not keeping the
+     * floating point value, but a value between 0 and 255 per channel,
+     * as it is storing the actual frame buffer, so there is a more big different
+     * between the value.
+     */
+    set_equal_precision(0.005);
+
+    Colour col = image.getPixel(5, 5);
+
+    ASSERT_EQ(col, Colour(0.38066, 0.47583, 0.2855));
+
+    set_equal_precision(FLT_EPSILON);
+}

tests/ch7_test.cpp

@@ -0,0 +1,83 @@
+/*
+ *  DoRayMe - a quick and dirty Raytracer
+ *  Render test for chapter 5 "Put it together".
+ *
+ *  Created by Manoël Trapier
+ *  Copyright (c) 2020 986-Studio.
+ *
+ */
+#include <world.h>
+#include <light.h>
+#include <sphere.h>
+#include <material.h>
+#include <colour.h>
+#include <canvas.h>
+#include <camera.h>
+#include <transformation.h>
+
+int main()
+{
+    /* First we need to construct the world */
+    Sphere floor = Sphere();
+    floor.setTransform(scaling(10, 0.01, 10));
+    floor.material.colour = Colour(1, 0.9, 0.9);
+    floor.material.specular = 0;
+
+    Sphere left_wall = Sphere();
+    left_wall.setTransform(translation(0, 0, 5) *
+                        rotationY(-M_PI / 4) * rotationX((M_PI / 2)) *
+                        scaling(10, 0.01, 10));
+    left_wall.material = floor.material;
+
+    Sphere right_wall = Sphere();
+    right_wall.setTransform(translation(0, 0, 5) *
+                           rotationY(M_PI / 4) * rotationX((M_PI / 2)) *
+                           scaling(10, 0.01, 10));
+    right_wall.material = floor.material;
+
+    Sphere middle = Sphere();
+    middle.setTransform(translation(-0.5, 1, 0.5));
+    middle.material.colour = Colour(0.1, 1, 0.5);
+    middle.material.diffuse = 0.7;
+    middle.material.specular = 0.3;
+
+    Sphere right = Sphere();
+    right.setTransform(translation(1.5, 0.5, -0.5) * scaling(0.5, 0.5, 0.5));
+    right.material.colour = Colour(0.5, 1, 0.1);
+    right.material.diffuse = 0.7;
+    right.material.specular = 0.3;
+
+    Sphere left = Sphere();
+    left.setTransform(translation(-1.5, 0.33, -0.75) * scaling(0.33, 0.33, 0.33));
+    left.material.colour = Colour(1, 0.8, 0.1);
+    left.material.diffuse = 0.7;
+    left.material.specular = 0.3;
+
+    World w = World();
+
+    w.addObject(&floor);
+    w.addObject(&left_wall);
+    w.addObject(&right_wall);
+    w.addObject(&middle);
+    w.addObject(&left);
+    w.addObject(&right);
+
+    /* Add light */
+    Light light = Light(POINT_LIGHT, Point(-10, 10, -10), Colour(1, 1, 1));
+
+    w.addLight(&light);
+
+    /* Set the camera */
+    Camera camera = Camera(1000, 500, M_PI / 3);
+    camera.setTransform(viewTransform(Point(0, 1.5, -5),
+                                      Point(0, 1, 0),
+                                      Vector(0, 1, 0)));
+
+    /* Now render it */
+    Canvas image = camera.render(w);
+
+    image.SaveAsPNG("ch7_test.png");
+
+
+    return 0;
+}