create basic honey_camera

3 files changed, 95 insertions, 1 deletions

diff --git a/include/camera.h b/include/camera.h
new file mode 100644
index 0000000..983dae8
--- /dev/null
+++ b/include/camera.h
@@ -0,0 +1,93 @@
+#ifndef HONEY_CAMERA_H
+#define HONEY_CAMERA_H
+
+/* @file camera.h
+ *
+ * @brief Define the basic honey_camera struct, associated functions,
+ * and common camera variants.
+ */
+
+#include "common.h"
+
+enum honey_camera_projection {
+  HONEY_PERSPECTIVE,
+  HONEY_ORTHOGRAPHIC,
+};
+
+typedef struct {
+  vec3 position;
+  vec3 angle; /* pitch, yaw, roll */
+  vec3 look_direction;
+  vec3 up;
+  vec3 right;
+  mat4 view;
+  mat4 projection;
+  enum honey_camera_projection projection_type;
+  float aspect_ratio;
+  float near, far;
+  float fov;
+  float ortho_left;
+  float ortho_right;
+  float ortho_top;
+  float ortho_bottom;
+} honey_camera;
+
+/** @brief Create a new camera.
+ *
+ * @param[out] camera Pointer to the destination honey_camera.
+ * @param[in] position The position of the camera.
+ * @param[in] angle The Euler angles (pitch, yaw, roll) of the camera.
+ * @param[in] projection The type of projection to use.
+ * @param[in] projection_parameters The parameters to use for the projection matrix.
+ * Use honey_perspective_parameters for a perspective projection and
+ * honey_orthographic_parameters for an orthographic projection.
+ */
+void honey_camera_new(honey_camera* camera,
+                      vec3 position,
+                      vec3 angle,
+                      enum honey_camera_projection projection_type,
+                      float aspect_ratio,
+                      float near, float far,
+                      float fov,
+                      float left, float right, float top, float bottom);
+
+void honey_camera_new_perspective(honey_camera* camera,
+                                  vec3 position,
+                                  vec3 angle,
+                                  float aspect_ratio,
+                                  float near, float far,
+                                  float fov);
+
+void honey_camera_new_orthographic(honey_camera* camera,
+                                   vec3 position,
+                                   vec3 angle,
+                                   float near, float far,
+                                   float left, float right, float top, float bottom);
+
+/** @brief (Re-)Calculate a camera's look_direction.
+ *
+ * @param[in] Pointer to the camera to re-calculate.
+ */
+void honey_camera_calculate_look_direction(honey_camera* camera);
+
+void honey_camera_calculate_up(honey_camera* camera);
+void honey_camera_calculate_right(honey_camera* camera);
+
+/** @brief (Re-)Calculate a camera's view matrix. 
+ *
+ * This function need only be called when the camera has been moved in some way.
+ *
+ * @param[in] camera Pointer to the camera to re-calculate.
+ */
+void honey_camera_calculate_view(honey_camera* camera);
+
+/** @brief (Re-)Calculate a camera's projection matrix.
+ *
+ * This function need only be called when the projection has changes in some way.
+ * Most commonly, this would be changing the FOV.
+ *
+ * @param[in] camera Pointer to the camera to re-calculate.
+ */
+void honey_camera_calculate_projection(honey_camera* camera);
+
+#endif
diff --git a/include/honey.h b/include/honey.h
index 3cddabc..3dbc5ab 100644
--- a/include/honey.h
+++ b/include/honey.h
@@ -6,6 +6,7 @@
  * @brief Defines the basic loading and callback functions. 
 */
 
+#include "camera.h"
 #include "common.h"
 #include "mesh.h"
 #include "primitives.h"
diff --git a/include/shader.h b/include/shader.h
index 610322e..cbef3de 100644
--- a/include/shader.h
+++ b/include/shader.h
@@ -52,7 +52,7 @@ void honey_shader_set_int(honey_shader shader,
  */
 void honey_shader_set_mat4(honey_shader shader,
                            char* matrix_name,
-                           float* matrix);
+                           mat4 matrix);
 
 /** @brief Use a shader.
  */