Implement basic clipping

jamieleecho · Jan 1, 2024 · 687d858 · 687d858
1 parent f21412e
commit 687d858
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Showing 2 changed files with 23 additions and 6 deletions.
diff --git a/game/levels/02-space.c b/game/levels/02-space.c
@@ -21,11 +21,17 @@ void SpaceInit() {
 
 
 byte SpaceCalculateBkgrndNewXY() {
+    sword minX = 2 * DynospriteDirectPageGlobalsPtr->Gfx_BkgrndNewX;
+    sword maxX = minX + 320;
+    sword minY = DynospriteDirectPageGlobalsPtr->Gfx_BkgrndNewY;
+    sword maxY = minY + 200;
+
     // Iterate through all active universal objects
     DynospriteCOB *obj = DynospriteDirectPageGlobalsPtr->Obj_CurrentTablePtr;
     DynospriteCOB *lastObj = obj + DynospriteDirectPageGlobalsPtr->Obj_NumCurrent;
-    sword xoffset = DynospriteDirectPageGlobalsPtr->Gfx_BkgrndNewX + 79;
-    sword yoffset = DynospriteDirectPageGlobalsPtr->Gfx_BkgrndNewY + 100;
+    sword xoffset = 2 * (DynospriteDirectPageGlobalsPtr->Gfx_BkgrndNewX + 79);
+    sword yoffset = DynospriteDirectPageGlobalsPtr->Gfx_BkgrndNewY + 99;
+
     for(; obj<lastObj; obj++) {
         if ((obj->active & OBJECT_ACTIVE) == 0) {
             continue;
@@ -36,8 +42,19 @@ byte SpaceCalculateBkgrndNewXY() {
             continue;
         }
         word depth = uobj->depth - 1;
-        obj->globalX = uobj->position[0] + ((uobj->position[0] / 2) - xoffset) * depth;
+        obj->globalX = uobj->position[0] + (uobj->position[0] - xoffset) * depth;
         obj->globalY = uobj->position[1] + (uobj->position[1] - yoffset) * depth;
+
+        sword globalXMin = obj->globalX + uobj->boundingBox[0];
+        sword globalYMin = obj->globalY + uobj->boundingBox[1];
+        sword globalXMax = obj->globalX + uobj->boundingBox[2];
+        sword globalYMax = obj->globalY + uobj->boundingBox[3];
+        if ((globalXMin < minX) || (globalYMin < minY) ||
+            (globalXMax >= maxX) || (globalYMax > maxY)) {
+            obj->active = obj->active & ~OBJECT_DRAW_ACTIVE;
+        } else {
+            obj->active = obj->active | OBJECT_DRAW_ACTIVE;
+        }
     }
 
     return 0;

diff --git a/game/levels/02-space.json b/game/levels/02-space.json
@@ -77,7 +77,7 @@
       "Active": 3,
       "globalX": 160,
       "globalY": 120,
-      "InitData": [0, 3, 0, 18, 0, 13, 0, 250, 0, 150]
+      "InitData": [0, 3, 244, 244, 12, 10, 0, 250, 0, 150]
     },
 
     {
@@ -87,7 +87,7 @@
       "Active": 3,
       "globalX": 20,
       "globalY": 100,
-      "InitData": [0, 2, 0, 9, 0, 9, 0, 245, 0, 150, 0, 0, 0, 0]
+      "InitData": [0, 2, 248, 248, 8, 8, 0, 245, 0, 150, 0, 0, 0, 0]
     },
 
     {
@@ -97,7 +97,7 @@
       "Active": 3,
       "globalX": 80,
       "globalY": 95,
-      "InitData": [0, 1, 0, 9, 0, 9, 0, 160, 0, 100]
+      "InitData": [0, 1, 248, 248, 8, 8, 0, 160, 0, 100]
     }
   ]
 }