tests: add a few test for mat4

.gitignore

@@ -71,3 +71,4 @@ win/Debug
 cglm-test-ios*
 /cglm.pc
 test-driver
+Default-568h@2x.png

include/cglm/mat4.h

@@ -446,6 +446,9 @@ glm_mat4_quat(mat4 m, versor dest) {
 /*!
  * @brief multiply vector with mat4
  *
+ * actually the result is vec4, after multiplication the last component
+ * is trimmed. if you need it don't use this func.
+ *
  * @param[in]  m    mat4(affine transform)
  * @param[in]  v    vec3
  * @param[in]  last 4th item to make it vec4

test/src/test_mat4.c

@@ -7,9 +7,6 @@
 
 #include "test_common.h"
 
-#define m 4
-#define n 4
-
 #define A_MATRIX  {{1,2,3,4},{5,6,7,8},{9,10,11,12},{13,14,15,16}}
 #define A_MATRIX3 {{1,2,3},{5,6,7},{9,10,11}}
 
@@ -141,9 +138,9 @@ TEST_IMPL(glm_mat4_mul) {
   test_rand_mat4(m2);
 
   glm_mat4_mul(m1, m2, m3);
-  for (i = 0; i < m; i++) {
+  for (i = 0; i < 4; i++) {
-    for (j = 0; j < n; j++) {
+    for (j = 0; j < 4; j++) {
-      for (k = 0; k < m; k++)
+      for (k = 0; k < 4; k++)
         /* column-major */
         m4[i][j] += m1[k][j] * m2[i][k];
     }
@@ -159,22 +156,85 @@ TEST_IMPL(glm_mat4_mul) {
 }
 
 TEST_IMPL(glm_mat4_mulN) {
+  mat4 res1, res2;
+  mat4 m1 = A_MATRIX;
+  mat4 m2 = A_MATRIX;
+  mat4 m3 = A_MATRIX;
+
+  mat4 *matrices[] = {
+    &m1, &m2, &m3
+  };
+
+  glm_mat4_mulN(matrices, sizeof(matrices) / sizeof(matrices[0]), res1);
+
+  glm_mat4_mul(*matrices[0], *matrices[1], res2);
+  glm_mat4_mul(res2, *matrices[2], res2);
+
+  ASSERTIFY(test_assert_mat4_eq(res1, res1))
+
   TEST_SUCCESS
 }
 
 TEST_IMPL(glm_mat4_mulv) {
+  vec4 res;
+  mat4 mat = A_MATRIX;
+  vec4 v = {1.0f, 2.0f, 3.0f, 4.0f};
+  int  i;
+
+  glm_mat4_mulv(mat, v, res);
+
+  for (i = 0; i < 4; i++) {
+    ASSERT(glm_eq(res[i],
+                  v[0] * mat[0][i]
+                + v[1] * mat[1][i]
+                + v[2] * mat[2][i]
+                + v[3] * mat[3][i]))
+  }
+
   TEST_SUCCESS
 }
 
 TEST_IMPL(glm_mat4_mulv3) {
+  vec4  res;
+  mat4  mat = A_MATRIX;
+  vec3  v = {1.0f, 2.0f, 3.0f};
+  float last;
+  int   i;
+
+  last = 1.0f;
+
+  glm_mat4_mulv3(mat, v, last, res);
+
+  for (i = 0; i < 3; i++) {
+    ASSERT(glm_eq(res[i],
+                  v[0] * mat[0][i]
+                  + v[1] * mat[1][i]
+                  + v[2] * mat[2][i]
+                  + last * mat[3][i]))
+  }
+
   TEST_SUCCESS
 }
 
 TEST_IMPL(glm_mat4_trace) {
+  mat4  mat = A_MATRIX;
+  float trace;
+
+  trace = glm_mat4_trace(mat);
+
+  ASSERT(glm_eq(trace, mat[0][0] + mat[1][1] + mat[2][2] + mat[3][3]))
+
   TEST_SUCCESS
 }
 
 TEST_IMPL(glm_mat4_trace3) {
+  mat4  mat = A_MATRIX;
+  float trace;
+
+  trace = glm_mat4_trace3(mat);
+
+  ASSERT(glm_eq(trace, mat[0][0] + mat[1][1] + mat[2][2]))
+
   TEST_SUCCESS
 }