Fixed mtx_transpose(), using (3-i).

source/maths/mtx_transpose.c

@@ -3,13 +3,13 @@
 void Mtx_Transpose(C3D_Mtx* out)
 {
 	float swap;
-	for (int i = 0; i < 4; i++)
+	for (int i = 0; i <= 2; i++)
 	{
-		for (int j = i+1; j < 4; j++)
+		for (int j = 2-i; j >= 0; j--)
 		{
-			swap = out->r[j].c[i];
+			swap = out->r[i].c[j];
-			out->r[j].c[i] = out->r[i].c[j];
+			out->r[i].c[j] = out->r[3-j].c[3-i];
-			out->r[i].c[j] = swap;
+			out->r[3-j].c[3-i] = swap;
 		}
 	}
 }

test/3ds/source/main.cpp

@@ -840,6 +840,57 @@ void ortho_test()
   C3D_RenderTargetDelete(tex);
 }
 
+void transpose_test()
+{
+  C3D_Mtx          modelView;
+  
+  std::printf("\n");
+  
+  Mtx_Identity(&modelView);
+  Mtx_Translate(&modelView, (rand() % 5) + 5.0f, (rand() % 5) + 5.0f, (rand() % 5) + 5.0f, true);
+  
+  std::printf("Random Translation:\n");
+  for (int i = 0; i < 16; i++)
+  {
+	  std::printf("%.2f  ", modelView.m[i]);
+	  if (i % 4 == 3)
+		  std::printf("\n");
+  }
+  
+  Mtx_Transpose(&modelView);
+  
+  std::printf("Random Translation Transposed:\n");
+  for (int i = 0; i < 16; i++)
+  {
+	  std::printf("%.2f  ", modelView.m[i]);
+	  if (i % 4 == 3)
+		  std::printf("\n");
+  }
+  
+  Mtx_Transpose(&modelView);
+  
+  std::printf("Rand-Trans Transposed Transposed:\n");
+  for (int i = 0; i < 16; i++)
+  {
+	  std::printf("%.2f  ", modelView.m[i]);
+	  if (i % 4 == 3)
+		  std::printf("\n");
+  }
+  
+
+  while(aptMainLoop())
+  {
+    gspWaitForVBlank();
+
+    hidScanInput();
+    u32 down = hidKeysDown();
+    if(down & (KEY_START|KEY_SELECT))
+      break;
+  }
+}
+
+
+
 typedef struct
 {
   const char *name;
@@ -854,6 +905,7 @@ test_t tests[] =
   { "Mtx_Persp",           persp_test,       },
   { "Mtx_PerspStereo",     stereo_test,      },
   { "Mtx_Ortho",           ortho_test,       },
+  { "Mtx_Transpose",       transpose_test,   },
 };
 
 const size_t num_tests = sizeof(tests)/sizeof(tests[0]);