Add tests for matrix module.

2 files changed, 64 insertions, 0 deletions

diff --git a/Makefile.am b/Makefile.am
index 4dc96a7..767e76d 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -103,6 +103,7 @@ SOURCES = 					\
 
 TESTS =						\
   tests/vector.scm				\
+  tests/matrix.scm				\
   tests/array-list.scm				\
   tests/heap.scm				\
   tests/quadtree.scm				\
diff --git a/tests/matrix.scm b/tests/matrix.scm
new file mode 100644
index 0000000..7f36280
--- /dev/null
+++ b/tests/matrix.scm
@@ -0,0 +1,63 @@
+;;; Chickadee Game Toolkit
+;;; Copyright © 2022 David Thompson <dthompson2@worcester.edu>
+;;;
+;;; Chickadee is free software: you can redistribute it and/or modify
+;;; it under the terms of the GNU General Public License as published
+;;; by the Free Software Foundation, either version 3 of the License,
+;;; or (at your option) any later version.
+;;;
+;;; Chickadee is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+;;; General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with this program.  If not, see
+;;; <http://www.gnu.org/licenses/>.
+
+(define-module (tests matrix)
+  #:use-module (tests utils)
+  #:use-module (srfi srfi-64)
+  #:use-module (chickadee math)
+  #:use-module (chickadee math matrix)
+  #:use-module (chickadee math quaternion)
+  #:use-module (chickadee math vector))
+
+(with-tests "matrix"
+  (test-group "4x4 matrices"
+    (test-group "multiplication"
+      (test-assert "identity"
+        (let ((m (make-matrix4 0 1 2 3
+                               4 5 6 7
+                               8 9 0 1
+                               2 3 4 5)))
+          (matrix4= m (matrix4* (make-identity-matrix4) m))))
+      (test-assert "inverse"
+        ;; Using whole numbers to avoid floating point precision
+        ;; issues where the resulting identity matrix has values very
+        ;; close to 1.0 (like 0.9999999403953552) but not exactly,
+        ;; causing the test to fail.
+        (let ((m (matrix4-scale (vec3 2 3 4))))
+          (matrix4= (make-identity-matrix4)
+                    (matrix4* m (matrix4-inverse m))))))
+    (test-group "transformation"
+      (test-assert "identity (vec2)"
+        (let ((v (vec2 1 2)))
+          (vec2= v (matrix4-transform-vec2 (make-identity-matrix4) v))))
+      (test-assert "identity (vec3)"
+        (let ((v (vec3 1 2 3)))
+          (vec3= v (matrix4-transform-vec3 (make-identity-matrix4) v))))
+      (test-assert "translate"
+        (vec3= (vec3 5 7 9)
+               (matrix4-transform-vec3 (matrix4-translate (vec3 4 5 6))
+                                       (vec3 1 2 3))))
+      (test-assert "scale"
+        (vec3= (vec3 6 12 20)
+               (matrix4-transform-vec3 (matrix4-scale (vec3 3 4 5))
+                                       (vec3 2 3 4))))
+      (test-assert "rotate"
+        (vec3= (vec3 0 1 0)
+               (matrix4-transform-vec3 (matrix4-rotate
+                                        (rotation->quaternion (vec3 0 0 -1)
+                                                              (/ pi 2)))
+                                       (vec3 1 0 0)))))))