GS/TC: Adjust how we handle merging targets in PreloadTarget.

If the two targets are misaligned, it's likely a relocation, so we can just kill the old target.
Kill targets that are overlapping new targets, but ignore the copy if the old target is dirty  because we favour GS memory.
Also check for width offset and adjust width accordingly using the offset.

pcsx2/GS/Renderers/HW/GSTextureCache.cpp

@@ -2605,6 +2605,17 @@ bool GSTextureCache::PreloadTarget(GIFRegTEX0 TEX0, const GSVector2i& size, cons
 				if (dst != t && t->m_TEX0.TBW == dst->m_TEX0.TBW && t->m_TEX0.PSM == dst->m_TEX0.PSM && t->m_TEX0.TBW > 4)
 					if (t->Overlaps(dst->m_TEX0.TBP0, dst->m_TEX0.TBW, dst->m_TEX0.PSM, dst->m_valid))
 					{
+						// If the two targets are misaligned, it's likely a relocation, so we can just kill the old target.
+						// Kill targets that are overlapping new targets, but ignore the copy if the old target is dirty  because we favour GS memory.
+						if (((((t->m_TEX0.TBP0 - dst->m_TEX0.TBP0) >> 5) % dst->m_TEX0.TBW) != 0) && !t->m_dirty.empty())
+						{
+							InvalidateSourcesFromTarget(t);
+							i = list.erase(j);
+							delete t;
+
+							continue;
+						}
+
 						// could be overwriting a double buffer, so if it's the second half of it, just reduce the size down to half.
 						if (((((t->UnwrappedEndBlock() + 1) - t->m_TEX0.TBP0) >> 1) + t->m_TEX0.TBP0) == dst->m_TEX0.TBP0)
 						{
@@ -2628,34 +2639,37 @@ bool GSTextureCache::PreloadTarget(GIFRegTEX0 TEX0, const GSVector2i& size, cons
 								continue;
 							}
 
-							const int dst_offset = ((((t->m_TEX0.TBP0 - dst->m_TEX0.TBP0) >> 5) / dst->m_TEX0.TBW) * GSLocalMemory::m_psm[t->m_TEX0.PSM].pgs.y);
-							const int dst_offset_scaled = dst_offset * dst->m_scale;
-							const GSVector4i dst_rect = GSVector4i(t->m_valid.x, dst_offset, t->m_valid.z, dst_offset + overlapping_pages_height);
-							if (((!hw_clear && (preserve_target || preload)) || dst_rect.rintersect(draw_rect).rempty()) && dst->GetScale() == t->GetScale())
+							const int dst_offset_width = (((t->m_TEX0.TBP0 - dst->m_TEX0.TBP0) >> 5) % dst->m_TEX0.TBW) * GSLocalMemory::m_psm[t->m_TEX0.PSM].pgs.x;
+							const int dst_offset_height = ((((t->m_TEX0.TBP0 - dst->m_TEX0.TBP0) >> 5) / dst->m_TEX0.TBW) * GSLocalMemory::m_psm[t->m_TEX0.PSM].pgs.y);
+							const int dst_offset_scaled_width = dst_offset_width * dst->m_scale;
+							const int dst_offset_scaled_height = dst_offset_height * dst->m_scale;
+							const GSVector4i dst_rect_scale = GSVector4i(t->m_valid.x, dst_offset_height, t->m_valid.z, dst_offset_height + overlapping_pages_height);
+							if (((!hw_clear && (preserve_target || preload)) || dst_rect_scale.rintersect(draw_rect).rempty()) && dst->GetScale() == t->GetScale())
 							{
-								const int copy_width = (t->m_texture->GetWidth()) > (dst->m_texture->GetWidth()) ? (dst->m_texture->GetWidth()) : t->m_texture->GetWidth();
+								const int copy_width = ((t->m_texture->GetWidth()) > (dst->m_texture->GetWidth()) ? (dst->m_texture->GetWidth()) : t->m_texture->GetWidth()) - dst_offset_scaled_width;
 								const int copy_height = overlapping_pages_height * t->m_scale;
 
-								GL_INS("RT double buffer copy from FBP 0x%x, %dx%d => %d,%d", t->m_TEX0.TBP0, copy_width, copy_height, 0, dst_offset_scaled);
+								GL_INS("RT double buffer copy from FBP 0x%x, %dx%d => %d,%d", t->m_TEX0.TBP0, copy_width, copy_height, 0, dst_offset_scaled_height);
 
 								pxAssert(copy_width <= dst->GetTexture()->GetWidth() && copy_height <= dst->GetTexture()->GetHeight() &&
 										 copy_width <= t->GetTexture()->GetWidth() && copy_height <= t->GetTexture()->GetHeight());
 
-								pxAssert(dst_offset_scaled > 0);
+								pxAssert(dst_offset_scaled_height > 0);
 
 								// Clear the dirty first
+								t->Update();
 								dst->Update();
 								// Invalidate has been moved to after DrawPrims(), because we might kill the current sources' backing.
 								if (!t->m_valid_rgb || !(t->m_valid_alpha_high || t->m_valid_alpha_low) || t->m_scale != dst->m_scale)
 								{
 									const GSVector4 src_rect = GSVector4(0, 0, copy_width, copy_height) / (GSVector4(t->m_texture->GetSize()).xyxy());
-									const GSVector4 dst_rect = GSVector4(0, dst_offset, copy_width, dst_offset + copy_height);
+									const GSVector4 dst_rect = GSVector4(dst_offset_scaled_width, dst_offset_scaled_height, dst_offset_scaled_width + copy_width, dst_offset_scaled_width + copy_height);
 									g_gs_device->StretchRect(t->m_texture, src_rect, dst->m_texture, dst_rect, t->m_valid_rgb, t->m_valid_rgb, t->m_valid_rgb, t->m_valid_alpha_high || t->m_valid_alpha_low);
 								}
 								else
 								{
 									// Invalidate has been moved to after DrawPrims(), because we might kill the current sources' backing.
-									g_gs_device->CopyRect(t->m_texture, dst->m_texture, GSVector4i(0, 0, copy_width, copy_height), 0, dst_offset_scaled);
+									g_gs_device->CopyRect(t->m_texture, dst->m_texture, GSVector4i(0, 0, copy_width, copy_height), dst_offset_scaled_width, dst_offset_scaled_height);
 								}
 							}