1 files changed, 20 insertions, 0 deletions
diff --git a/frontend/_shared/math/mat4.js b/frontend/_shared/math/mat4.js
index 6ab29e2..d31a20e 100644
--- a/frontend/_shared/math/mat4.js
+++ b/frontend/_shared/math/mat4.js
@@ -40,4 +40,24 @@ function scaleMatrix(m, x, y, z) {
     m[5] = m[5] * y;
     m[10] = m[10] * z;
     return m;
+}
+
+function multMat4ByVec2(matrix, vec) {
+    var lInnerVec = {...vec};
+    lInnerVec.z = 0.0;
+    lInnerVec.w = 1.0;
+
+    return {
+        x: lInnerVec.x * matrix[0] + lInnerVec.y * matrix[4] + lInnerVec.z * matrix[8] + lInnerVec.w * matrix[12],
+        y: lInnerVec.x * matrix[1] + lInnerVec.y * matrix[5] + lInnerVec.z * matrix[9] + lInnerVec.w * matrix[13]
+    };
+}
+
+function multMat4ByVec4(matrix, vec) {
+    return {
+        x: vec.x * matrix[0] + vec.y * matrix[4] + vec.z * matrix[8] + vec.w * matrix[12],
+        y: vec.x * matrix[1] + vec.y * matrix[5] + vec.z * matrix[9] + vec.w * matrix[13],
+        z: vec.x * matrix[2] + vec.y * matrix[6] + vec.z * matrix[10] + vec.w * matrix[14],
+        w: vec.x * matrix[3] + vec.y * matrix[7] + vec.z * matrix[11] + vec.w * matrix[15]
+    };
 }
 \ No newline at end of file