Fixed code to avoid arbitrary negative signs. Mode7 now uses an ACW a…

…ngle.
32blit · Aug 27, 2022 · 42e471b · 42e471b
1 parent 3b74f0f
commit 42e471b
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Showing 2 changed files with 5 additions and 5 deletions.
diff --git a/32blit/graphics/mode7.cpp b/32blit/graphics/mode7.cpp
@@ -34,7 +34,7 @@ namespace blit {
     Vec2 v(w - pos);
     v.normalize();
     Vec2 f(0, -1);
-    f *= Mat3::rotation(-angle);
+    f *= Mat3::rotation(angle);
 
     float wd = (w - pos).length();
     float dot = f.dot(v);
@@ -72,7 +72,7 @@ namespace blit {
    */
   Vec2 screen_to_world(Vec2 s, float fov, float angle, Vec2 pos, float near, float far, Rect viewport) {
     Vec2 forward(0, -1);
-    forward *= Mat3::rotation(-angle);
+    forward *= Mat3::rotation(angle);
 
     Vec2 left = forward;
     left *= Mat3::rotation(-(fov / 2.0f));

diff --git a/examples/flight/flight.cpp b/examples/flight/flight.cpp
@@ -126,7 +126,7 @@ std::vector<DrawObject> drawObjects (std::vector<object> objects) {
     Vec2 vo = (o.pos - pos);
     vo.normalize();
     Vec2 forward(0, -1);
-    forward *= Mat3::rotation(-angle);
+    forward *= Mat3::rotation(angle);
 
     // TODO: provide a "is_point_in_frustrum" check
     if(forward.dot(vo) > 0) { // check if object is in front of us
@@ -223,7 +223,7 @@ void render(uint32_t time_ms) {
   screen.pixel(mtpos);
 
   Vec2 forward(0, -10);
-  forward *= Mat3::rotation(-angle);
+  forward *= Mat3::rotation(angle);
   screen.pen = Pen(255, 255, 255, 100);
   screen.line(mmpos, mmpos + forward);
 
@@ -282,7 +282,7 @@ void update(uint32_t time) {
   }
 
   angle += deg2rad(angle_delta);
-  Mat3 r = Mat3::rotation(-angle);
+  Mat3 r = Mat3::rotation(angle);
   pos = pos - (vel * r);
 
   if (pressed(Button::A) || (joystick.y > 0.0f)) {