[core] Refactoring transform state (#15956)

* [core] Refactoring transform state class

* [core] update matrix in transform, Fix precision

* [core] Make matrix mutable so that we only update them when needed

* [core] Add getters for matrices

2 files changed, 2 insertions, 2 deletions

diff --git a/src/mbgl/util/mat4.cpp b/src/mbgl/util/mat4.cpp
index 0ad0d371e5..2f7d35a5be 100644
--- a/src/mbgl/util/mat4.cpp
+++ b/src/mbgl/util/mat4.cpp
@@ -47,7 +47,7 @@ void identity(mat4& out) {
     out[15] = 1.0f;
 }
 
-bool invert(mat4& out, mat4& a) {
+bool invert(mat4& out, const mat4& a) {
     double a00 = a[0], a01 = a[1], a02 = a[2], a03 = a[3],
           a10 = a[4], a11 = a[5], a12 = a[6], a13 = a[7],
           a20 = a[8], a21 = a[9], a22 = a[10], a23 = a[11],
diff --git a/src/mbgl/util/mat4.hpp b/src/mbgl/util/mat4.hpp
index 2adeba8821..438771949f 100644
--- a/src/mbgl/util/mat4.hpp
+++ b/src/mbgl/util/mat4.hpp
@@ -32,7 +32,7 @@ using mat4 = std::array<double, 16>;
 namespace matrix {
 
 void identity(mat4& out);
-bool invert(mat4& out, mat4& a);
+bool invert(mat4& out, const mat4& a);
 void ortho(mat4& out, double left, double right, double bottom, double top, double near, double far);
 void perspective(mat4& out, double fovy, double aspect, double near, double far);
 void copy(mat4& out, const mat4& a);