From 8e684dc0c76708e3174f005aebcaabc144b85500 Mon Sep 17 00:00:00 2001
From: chai <chaifix@163.com>
Date: Thu, 5 Dec 2019 09:21:26 +0800
Subject: =?UTF-8?q?*=E8=83=8C=E9=9D=A2=E5=89=94=E9=99=A4?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/math/math.c   |  3 +--
 src/math/math.h   |  1 +
 src/math/matrix.c | 12 ++++++++++++
 src/math/vec3.c   |  4 ++--
 4 files changed, 16 insertions(+), 4 deletions(-)

(limited to 'src/math')

diff --git a/src/math/math.c b/src/math/math.c
index 4cca29e..7d731f8 100644
--- a/src/math/math.c
+++ b/src/math/math.c
@@ -5,14 +5,13 @@ char printbuffer[2048] = { 0 };
 float rsqrt(float number) {
 	long i;
 	float x2, y;
-	const float threehalfs = 1.5F;
 
 	x2 = number * 0.5F;
 	y = number;
 	i = *(long *)&y;
 	i = 0x5f3759df - (i >> 1);
 	y = *(float *)&i;
-	y = y * (threehalfs - (x2 * y * y));
+	y = y * (1.5F - (x2 * y * y));
 	return y;
 }
 
diff --git a/src/math/math.h b/src/math/math.h
index 4498920..90c7521 100644
--- a/src/math/math.h
+++ b/src/math/math.h
@@ -211,6 +211,7 @@ void mat4_zero(Mat4* out);
 void mat4_setidentity(Mat4* out);
 void mat4_setfrustum(float l, float r, float b, float t, float n, float f, Mat4* out);
 void mat4_setperspective(float fov, float aspect, float near, float far, Mat4* out);
+void mat4_setortho(float l, float r, float b, float t, float n, float f, Mat4* out);
 void mat4_setscale(float kx, float ky, float kz, Mat4* out);
 void mat4_setposition(float x, float y, float z, Mat4* out);
 void mat4_setrotatez(float angle, Mat4* out);
diff --git a/src/math/matrix.c b/src/math/matrix.c
index 458f432..15a194d 100644
--- a/src/math/matrix.c
+++ b/src/math/matrix.c
@@ -61,6 +61,18 @@ void mat4_setidentity(Mat4* out) {
 	out->e33 = 1;
 }
 
+void mat4_setortho(float l, float r, float b, float t, float n, float f, Mat4* out) {
+	ssr_assert(out);
+	mat4_zero(out);
+	out->e00 = 2 / (r - l);
+	out->e03 = -(r + l) / (r - l);
+	out->e11 = 2 / (t - b);
+	out->e13 = -(t + b) / (t - b);
+	out->e22 = -2 / (f - n);
+	out->e23 = -(f + n) / (f - n);
+	out->e33 = 1;
+}
+
 void mat4_setfrustum(float l, float r, float b, float t, float n, float f, Mat4* out) {
 	ssr_assert(out);
 	mat4_zero(out);
diff --git a/src/math/vec3.c b/src/math/vec3.c
index 4d77b96..4ca8519 100644
--- a/src/math/vec3.c
+++ b/src/math/vec3.c
@@ -96,8 +96,8 @@ void vec3_multiply(Vec3* v1, Vec3* v2, Quat* out) {
 
 void vec3_normalize(Vec3* v, Vec3* out) {
 	ssr_assert(v && out);
-	//float mag = rsqrt(v->x * v->x + v->y * v->y + v->z * v->z);
-	float mag = 1.f / vec3_magnitude(v);
+	float mag = rsqrt(v->x * v->x + v->y * v->y + v->z * v->z);
+	//float mag = 1.f / vec3_magnitude(v);
 	out->x = v->x * mag;
 	out->y = v->y * mag;
 	out->z = v->z * mag;
-- 
cgit v1.1-26-g67d0