From 676a246a78c5219d20aa55f3e42ba1e4170b550c Mon Sep 17 00:00:00 2001
From: matthew <matthew@owens.tech>
Date: Tue, 18 Sep 2018 21:05:42 +0100
Subject: [PATCH] refactored camera code to seperate compilation unit
---
gl/camera.c | 70 +++++++++++++++++++++++++++++++++++++++++++++++++++++
gl/camera.h | 12 +++++++++
gl/main.c | 21 ++++++----------
3 files changed, 89 insertions(+), 14 deletions(-)
create mode 100644 gl/camera.c
create mode 100644 gl/camera.h
diff --git a/gl/camera.c b/gl/camera.c
new file mode 100644
index 0000000..5f571dd
--- /dev/null
+++ b/gl/camera.c
@@ -0,0 +1,70 @@
+#include "camera.h"
+#include <math.h>
+#include <stdlib.h>
+
+static vec3_t worldSpaceVec;
+static float aspectRatio = 16.f/9.f; // sane default for the aspect ratio
+
+typedef struct
+{
+ vec3_t from, to, up;
+ mat4_t camera, perspective, worldToScreen;
+} Camera_t;
+
+///TODO: figure out why this is failing
+mat4_t recalcPerspective(float hFovDeg, float near, float far)
+{
+ float vFovDeg = 2 * atan( tan(hFovDeg/2) * aspectRatio );
+ float vFovRad = vFovDeg * (M_PI/180.f);
+
+ return m4_perspective(vFovRad, aspectRatio, near, far);
+}
+
+void crpgCameraSetAR(float ar)
+{
+ aspectRatio = ar;
+}
+
+crpgCamera *crpgCameraNew(vec3_t from, vec3_t to, vec3_t up)
+{
+ // ensuring that the world doesn't go mental
+ worldSpaceVec = vec3(1, 1, -1);
+ Camera_t *ct = malloc(sizeof(Camera_t));
+ ct->from = from;
+ ct->to = to;
+ ct->up = up;
+ ct->camera = m4_look_at(from, to, up);
+ //ct->perspective = recalcPerspective(90.f, 1, 10);
+ ct->perspective = m4_perspective(60, aspectRatio, 1, 10);
+ ct->worldToScreen = m4_mul(ct->perspective, ct->camera);
+
+ crpgCamera *c = (crpgCamera *) ct;
+ return c;
+}
+
+void crpgCameraFree(crpgCamera *c)
+{
+ if(c == NULL){
+ return;
+ } else {
+ free(c);
+ }
+}
+
+void crpgCameraPan(crpgCamera *c, vec3_t pan)
+{
+ Camera_t *ct = (Camera_t *) c;
+ ct->from.x += pan.x;
+ ct->from.y += pan.y;
+ ct->from.z += pan.z;
+
+ // recalc camera matrices
+ ct->camera = m4_look_at(ct->from, ct->to, ct->up);
+ ct->worldToScreen = m4_mul(ct->perspective, ct->camera);
+}
+
+mat4_t *crpgCameraGetMat(crpgCamera *c)
+{
+ Camera_t *ct = (Camera_t *)c;
+ return &(ct->worldToScreen);
+}
diff --git a/gl/camera.h b/gl/camera.h
new file mode 100644
index 0000000..ed8d739
--- /dev/null
+++ b/gl/camera.h
@@ -0,0 +1,12 @@
+#ifndef CAMERA_H
+#define CAMERA_H
+#include "math_3d.h"
+#include <stdbool.h>
+typedef struct {} crpgCamera;
+
+crpgCamera *crpgCameraNew(vec3_t from, vec3_t to, vec3_t up);
+void crpgCameraFree(crpgCamera *c);
+void crpgCameraPan(crpgCamera *c, vec3_t pan);
+void crpgCameraSetAR(float ar);
+mat4_t *crpgCameraGetMat(crpgCamera *c);
+#endif//CAMERA_H
diff --git a/gl/main.c b/gl/main.c
index e7fafb2..83fdcaf 100644
--- a/gl/main.c
+++ b/gl/main.c
@@ -11,6 +11,7 @@
#include "math_3d.h"
#include "point.h"
#include "cube.h"
+#include "camera.h"
static SDL_Window *window = NULL;
static SDL_GLContext *context = NULL;
@@ -38,8 +39,8 @@ static float blendVal = 0.2f;
static crpgShader *shader = NULL;
static crpgTexture *tex[2];
static crpgCube *cubes[2];
-static mat4_t projection, transform, camera, world_to_screen;
-static vec3_t from, to, up, screenSpace, worldSpace;
+static crpgCamera *camera = NULL;
+static mat4_t transform;
static void initShapes()
{
@@ -97,18 +98,10 @@ static void initShapes()
static void initView()
{
- projection = m4_perspective(60, (float)screen_width/(float)screen_height, 1, 10);
- //from = vec3(0, 0.5, 2);
- from = vec3(0,0,4);
- to = vec3(0,0,0);
- up = vec3(0,1,0);
- camera = m4_look_at(from, to, up);
- worldSpace = vec3(1, 1, -1);
- world_to_screen = m4_mul(projection, camera);
- screenSpace = m4_mul_pos(world_to_screen, worldSpace);
-
- crpgCubeSetCamera(cubes[0], &world_to_screen);
- crpgCubeSetCamera(cubes[1], &world_to_screen);
+ crpgCameraSetAR((float)screen_width/(float)screen_height);
+ camera = crpgCameraNew(vec3(0,0,4), vec3(0,0,0), vec3(0,1,0));
+ crpgCubeSetCamera(cubes[0], crpgCameraGetMat(camera));
+ crpgCubeSetCamera(cubes[1], crpgCameraGetMat(camera));
glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LESS);
--
2.20.1