From ab2160bdd347f4cd827835f1687437d25fae94c6 Mon Sep 17 00:00:00 2001
From: jvech <jmvalenciae@unal.edu.co>
Date: Tue, 30 Aug 2022 11:30:04 -0500
Subject: feat: orthographic transformation added

---
 src/linear.c | 20 ++++++++++++++++++++
 src/linear.h |  1 +
 2 files changed, 21 insertions(+)

(limited to 'src')

diff --git a/src/linear.c b/src/linear.c
index 8bd58e8..062c103 100644
--- a/src/linear.c
+++ b/src/linear.c
@@ -47,6 +47,26 @@ linearPerspective(float FoV, float ratio, float near, float far)
     return out;
 }
 
+Mat4
+linearOrtho(float left, float right, float bottom, float top, float near, float far)
+{
+    Mat4 out = linearMat4Identity(1.0);
+
+    float width = right - left;
+    float height = top - bottom;
+    float depth = far - near;
+
+    out.matrix[0][0] = 2 / (width);
+    out.matrix[0][3] = - (right + left) / width;
+
+    out.matrix[1][1] = 2 / (height);
+    out.matrix[1][3] = - (top + bottom) / height;
+
+    out.matrix[2][2] = -2 / (depth);
+    out.matrix[2][2] = - (far + near) / depth;
+    return out;
+}
+
 Mat4
 linearTranslate(float T_x, float T_y, float T_z)
 {
diff --git a/src/linear.h b/src/linear.h
index 4ed2298..bd373f8 100644
--- a/src/linear.h
+++ b/src/linear.h
@@ -20,6 +20,7 @@ Mat4 linearTranslate(float translate_x, float translate_y, float translate_z);
 Mat4 linearScale(float scale_x, float scale_y, float scale_z);
 Mat4 linearRotate(float degree, float rotate_x, float rotate_y, float rotate_z);
 Mat4 linearPerspective(float FoV, float ratio, float near, float far);
+Mat4 linearOrtho(float left, float right, float bottom, float top, float near, float far);
 Mat4 linearLookAt(Vec3 position, Vec3 target, Vec3 up);
 
 Mat4 linearMat4Fill(float value);
-- 
cgit v1.2.3-70-g09d2