engine.math.camera source code

1 /*
2     Copyright © 2020, Luna Nielsen
3     Distributed under the 2-Clause BSD License, see LICENSE file.
4     
5     Authors: Luna Nielsen
6 */
7 module engine.math.camera;
8 import gl3n.linalg;
9 import engine;
10 
11 /**
12     Camera for 3D space
13 */
14 class Camera {
15 private:
16 
17     mat4 g_matrix() {
18         return mat4.perspective(cameraTargetWidth, cameraTargetHeight, fov, 0.1, 50) * transform.matrix;
19     }
20 
21 public:
22 
23     this() {
24         
25     }
26 
27     float fov = 90;
28 
29     /**
30         Transform of the position of the camera
31     */
32     Transform transform;
33 
34     /**
35         Create 3D camera
36     */
37     this(Transform transform = null) {
38         this.transform = transform is null ? new Transform() : transform;
39     }
40 
41     /**
42         The matrix for the camera
43     */
44     mat4 matrix() {
45         return g_matrix();
46     }
47 }
48 
49 /**
50     Orthographic camera for rendering UI
51 
52     TODO: extend camera as needed
53 */
54 class Camera2D {
55 private:
56     mat4 projection;
57 
58 public:
59 
60     this() {
61         position = vec2(0, 0);
62     }
63 
64     /**
65         Position of camera
66     */
67     vec2 position;
68 
69     /**
70         Matrix for this camera
71     */
72     mat4 matrix() {
73         int largestSize = max(kmViewportWidth, kmViewportHeight);
74         return 
75             mat4.orthographic(0f, cast(float)cameraTargetWidth, cast(float)cameraTargetHeight, 0, 0, largestSize) * 
76             mat4.translation(position.x, position.y, -10);
77     }
78 }
79 
80 private int cameraTargetWidth;
81 private int cameraTargetHeight;
82 
83 void kmSetCameraTargetSize(int width, int height) {
84     cameraTargetWidth = width;
85     cameraTargetHeight = height;
86 }
87 
88 int kmCameraViewWidth() {
89     return cameraTargetWidth;
90 }
91 
92 int kmCameraViewHeight() {
93     return cameraTargetHeight;
94 }