read proper depth values from the renderer (#124)

mm/2s2h/BenPort.cpp

@@ -610,12 +610,17 @@ extern "C" void Graph_ProcessGfxCommands(Gfx* commands) {
 
 float divisor_num = 0.0f;
 
+// Batch a coordinate to have its depth read later by OTRGetPixelDepth
 extern "C" void OTRGetPixelDepthPrepare(float x, float y) {
-    OTRGlobals::Instance->context->GetWindow()->GetPixelDepthPrepare(x, y);
+    // Invert the Y value to match the origin values used in the renderer
+    float adjustedY = SCREEN_HEIGHT - y;
+    OTRGlobals::Instance->context->GetWindow()->GetPixelDepthPrepare(x, adjustedY);
 }
 
 extern "C" uint16_t OTRGetPixelDepth(float x, float y) {
-    return OTRGlobals::Instance->context->GetWindow()->GetPixelDepth(x, y);
+    // Invert the Y value to match the origin values used in the renderer
+    float adjustedY = SCREEN_HEIGHT - y;
+    return OTRGlobals::Instance->context->GetWindow()->GetPixelDepth(x, adjustedY);
 }
 
 extern "C" uint32_t ResourceMgr_GetNumGameVersions() {

mm/include/functions.h

@@ -1323,6 +1323,9 @@ void osContGetReadData(OSContPad* pad);
 void PadMgr_ThreadEntry();
 void Heaps_Alloc(void);
 // #endregion
+// #region 2S2H [Port] New methods added for porting
+void Lights_GlowCheckPrepare(PlayState* play);
+// #endregion
 // #region 2S2H [Port] Stubbed methods
 void osSetThreadPri(OSThread* thread, OSPri p);
 OSPri osGetThreadPri(OSThread* t);

mm/src/code/sys_cfb.c

@@ -121,6 +121,9 @@ void* SysCfb_GetWorkBuffer(void) {
 }
 
 u16 SysCfb_GetZBufferPixel(s32 x, s32 y) {
+    // 2S2H [Port] Get the zbuffer pixel value from the renderer directly
+    return OTRGetPixelDepth(x, y);
+#if 0
     u16* zBuff = SysCfb_GetZBuffer();
     u16 val;
 
@@ -130,8 +133,12 @@ u16 SysCfb_GetZBufferPixel(s32 x, s32 y) {
         val = 0;
     }
     return val;
+#endif
 }
 
 s32 SysCfb_GetZBufferInt(s32 x, s32 y) {
-    return Environment_ZBufValToFixedPoint(SysCfb_GetZBufferPixel(x, y) << 2) >> 3;
+    // 2S2H [Port] The value from the renderer does not need to be converted to a fixed point
+    // Simply shifting is all we need to get the proper value
+    return SysCfb_GetZBufferPixel(x, y) >> 1;
+    // return Environment_ZBufValToFixedPoint(SysCfb_GetZBufferPixel(x, y) << 2) >> 3;
 }

mm/src/code/z_kankyo.c

@@ -490,6 +490,10 @@ void Environment_JumpForwardInTime(void);
 void Environment_GraphCallback(GraphicsContext* gfxCtx, void* arg) {
     PlayState* play = (PlayState*)arg;
 
+    // 2S2H [Port] Batch all the coordinates that need their depth checked by calling prepare
+    OTRGetPixelDepthPrepare(sSunDepthTestX, sSunDepthTestY);
+    Lights_GlowCheckPrepare(play);
+
     sSunScreenDepth = SysCfb_GetZBufferPixel(sSunDepthTestX, sSunDepthTestY);
     Lights_GlowCheck(play);
 }

mm/src/code/z_lights.c

@@ -372,6 +372,35 @@ Lights* Lights_New(GraphicsContext* gfxCtx, u8 ambientR, u8 ambientG, u8 ambient
     return lights;
 }
 
+// 2S2H [Port] Similar to Lights_GlowCheck, but only submits the coordinates to the depth prepare
+// for batching and then will be read after when Lights_GlowCheck is called
+void Lights_GlowCheckPrepare(PlayState* play) {
+    LightNode* light = play->lightCtx.listHead;
+
+    while (light != NULL) {
+        LightPoint* params = &light->info->params.point;
+
+        if (light->info->type == LIGHT_POINT_GLOW) {
+            Vec3f worldPos;
+            Vec3f projectedPos;
+            f32 invW;
+
+            worldPos.x = params->x;
+            worldPos.y = params->y;
+            worldPos.z = params->z;
+            Actor_GetProjectedPos(play, &worldPos, &projectedPos, &invW);
+
+            if ((projectedPos.z > 1) && (fabsf(projectedPos.x * invW) < 1) && (fabsf(projectedPos.y * invW) < 1)) {
+                s32 screenPosX = PROJECTED_TO_SCREEN_X(projectedPos, invW);
+                s32 screenPosY = PROJECTED_TO_SCREEN_Y(projectedPos, invW);
+                OTRGetPixelDepthPrepare(screenPosX, screenPosY);
+            }
+        }
+
+        light = light->next;
+    }
+}
+
 void Lights_GlowCheck(PlayState* play) {
     LightNode* light = play->lightCtx.listHead;