From 7a333a68c2f2f372d936c1efd900c315de627848 Mon Sep 17 00:00:00 2001
From: Malkierian <malkierian@gmail.com>
Date: Mon, 9 Dec 2024 10:16:14 -0700
Subject: [PATCH] Add check for render view to prevent drawing stars outside of
 it. Remove garbage star interp calculation.

---
 src/engine/fox_bg.c | 27 ++++++++-------------------
 1 file changed, 8 insertions(+), 19 deletions(-)

diff --git a/src/engine/fox_bg.c b/src/engine/fox_bg.c
index 9a4ce815..870a9699 100644
--- a/src/engine/fox_bg.c
+++ b/src/engine/fox_bg.c
@@ -258,21 +258,15 @@ void Background_DrawStarfield(void) {
             vx = (zCos * bx) + (zSin * by) + currentScreenWidth / 2.0f;
             vy = (-zSin * bx) + (zCos * by) + currentScreenHeight / 2.0f;
 
+            float thirdWidth = currentScreenWidth / 3;
+            float thirdHeight = currentScreenHeight / 3;
+
             // Check if the star is within the visible screen area with margin
-            if ((vx >= STAR_MARGIN) && (vx < currentScreenWidth - STAR_MARGIN) && (vy >= STAR_MARGIN) &&
-                (vy < currentScreenHeight - STAR_MARGIN)) {
+            if (vx >= (thirdWidth - STAR_MARGIN) && vx <= ((thirdWidth * 2) + STAR_MARGIN) &&
+                vy >= (thirdHeight - STAR_MARGIN) && vy <= ((thirdHeight * 2) + STAR_MARGIN)) {
 
-                // @port: Some garbage stars can be seen while scrolling faster, because of this
-                // we should skip interpolation when the stars warp from left to right.
-                u8 skipStarsInterpolation = (fabsf(vx - gStarPrevX[i]) > starfieldWidth / 2.0f) ||
-                                            (fabsf(vy - gStarPrevY[i]) > starfieldHeight / 2.0f);
-
-                if (skipStarsInterpolation) {
-                    FrameInterpolation_ShouldInterpolateFrame(false);
-                } else {
-                    FrameInterpolation_RecordOpenChild("Starfield", i);
-                    FrameInterpolation_RecordMarker(__FILE__, __LINE__);
-                }
+                FrameInterpolation_RecordOpenChild("Starfield", i);
+                FrameInterpolation_RecordMarker(__FILE__, __LINE__);
 
                 // Translate to (vx, vy) in ortho coordinates
                 Matrix_Push(&gGfxMatrix);
@@ -295,12 +289,7 @@ void Background_DrawStarfield(void) {
                 gSPDisplayList(gMasterDisp++, starDL);
                 Matrix_Pop(&gGfxMatrix);
 
-                if (skipStarsInterpolation) {
-                    FrameInterpolation_ShouldInterpolateFrame(true);
-                } else {
-                    // Pop the transform id
-                    FrameInterpolation_RecordCloseChild();
-                }
+                FrameInterpolation_RecordCloseChild();
 
                 gStarPrevX[i] = vx;
                 gStarPrevY[i] = vy;