From 59df9e87483c196a01f1a7bf55e279128b2073b6 Mon Sep 17 00:00:00 2001
From: Roz K <roz@rozk.net>
Date: Tue, 20 Sep 2022 02:54:59 +0200
Subject: [PATCH] Add mat4_projection and mat4_lookat.

---
 __init__.py  | 22 ++++++++++++++++++++++
 cpp/math.cpp | 16 ++++++++++++++++
 cpp/math.hpp | 12 ++++++++++++
 3 files changed, 50 insertions(+)

diff --git a/__init__.py b/__init__.py
index 8b64bf4..ad194d6 100644
--- a/__init__.py
+++ b/__init__.py
@@ -163,6 +163,28 @@ def mat3_mul_mat3(ret, a, b):
     assert len(ret) == 9 and len(a) == 9 and len(b) == 9
     _mat3_mul_mat3(_mat3(ret), _mat3(a), _mat3(b))
 
+_mat4_projection = _lib.rk_mat4_projection
+_mat4_projection.argtypes = (
+    _mat4_t, # ret
+    ctypes.c_float, # hfov
+    ctypes.c_float, # ratio
+    ctypes.c_float, # near
+    ctypes.c_float) # far
+
+def mat4_projection(ret, hfov, ratio, near, far):
+    assert len(ret) == 16
+    _mat4_projection(_mat4(ret), hfov, ratio, near, far)
+
+_mat4_lookat = _lib.rk_mat4_lookat
+_mat4_lookat.argtypes = (
+    _mat4_t, # ret
+    _vec3_t, # position
+    _vec3_t) # lookat
+
+def mat4_lookat(ret, position, lookat):
+    assert len(ret) == 16 and len(position) == 3 and len(lookat) == 3
+    _mat4_lookat(_mat4(ret), _vec3(position), _vec3(lookat))
+
 _mat4_mul_vec4 = _lib.rk_mat4_mul_vec4
 _mat4_mul_vec4.argtypes = (
     _vec4_t, # ret
diff --git a/cpp/math.cpp b/cpp/math.cpp
index 2d34ff3..23cdff3 100644
--- a/cpp/math.cpp
+++ b/cpp/math.cpp
@@ -38,6 +38,22 @@ void rk_mat3_mul_mat3(
     ret = a * b;
 }
 
+void rk_mat4_projection(
+    rk_mat4 & ret,
+    float hfov,
+    float ratio,
+    float near,
+    float far) {
+    ret = glm::perspectiveRH(hfov, ratio, near, far);
+}
+
+void rk_mat4_lookat(
+    rk_mat4 & ret,
+    rk_vec3 const & position,
+    rk_vec3 const & lookat) {
+    ret = glm::lookAtRH(position, lookat, glm::vec3(0.0f, 0.0f, 1.0f));
+}
+
 void rk_mat4_mul_vec4(
     rk_vec4 & ret,
     rk_mat4 const & a,
diff --git a/cpp/math.hpp b/cpp/math.hpp
index 0d82ee3..db35237 100644
--- a/cpp/math.hpp
+++ b/cpp/math.hpp
@@ -41,6 +41,18 @@ RK_EXPORT void rk_mat3_mul_mat3(
     rk_mat3 const & a,
     rk_mat3 const & b);
 
+RK_EXPORT void rk_mat4_projection(
+    rk_mat4 & ret,
+    float hfov,
+    float ratio,
+    float near,
+    float far);
+
+RK_EXPORT void rk_mat4_lookat(
+    rk_mat4 & ret,
+    rk_vec3 const & position,
+    rk_vec3 const & lookat);
+
 RK_EXPORT void rk_mat4_mul_vec4(
     rk_vec4 & ret,
     rk_mat4 const & a,