Redo mouse cursor handling

Aerofoil/GpColorCursor_Win32.cpp

@@ -1,58 +1,132 @@
-#include "GpCursor_Win32.h"
+/*
+  Portions of this file based on Simple DirectMedia Layer
+  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>
 
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+	 claim that you wrote the original software. If you use this software
+	 in a product, an acknowledgment in the product documentation would be
+	 appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+	 misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+#include "GpColorCursor_Win32.h"
+
+#include <stdint.h>
 #include <stdlib.h>
 #include <new>
+#include <algorithm>
 
-void GpCursor_Win32::Destroy()
+void GpColorCursor_Win32::Destroy()
 {
 	this->DecRef();
 }
 
-IGpCursor_Win32 *GpCursor_Win32::Load(const wchar_t *path)
+IGpCursor_Win32 *GpColorCursor_Win32::Create(size_t width, size_t height, const void *pixelDataRGBA, size_t hotSpotX, size_t hotSpotY)
 {
-	HANDLE imageH = LoadImageW(nullptr, path, IMAGE_CURSOR, 0, 0, LR_LOADFROMFILE);
+	const size_t paddingBits = (sizeof(void*) * 8);
 
-	if (imageH == nullptr)
+	BITMAPV4HEADER bmp;
+
+	memset(&bmp, 0, sizeof(bmp));
+	bmp.bV4Size = sizeof(bmp);
+	bmp.bV4Width = width;
+	bmp.bV4Height = -static_cast<LONG>(height);
+	bmp.bV4Planes = 1;
+	bmp.bV4BitCount = 32;
+	bmp.bV4V4Compression = BI_BITFIELDS;
+	bmp.bV4AlphaMask = 0xFF000000;
+	bmp.bV4RedMask = 0x00FF0000;
+	bmp.bV4GreenMask = 0x0000FF00;
+	bmp.bV4BlueMask = 0x000000FF;
+
+	size_t maskPitch = width + paddingBits - 1;
+	maskPitch -= maskPitch % paddingBits;
+
+	LPVOID maskBits = malloc(maskPitch * height);
+	if (!maskBits)
 		return nullptr;
 
-	HCURSOR cursor = reinterpret_cast<HCURSOR>(imageH);
-	void *storage = malloc(sizeof(GpCursor_Win32));
+	memset(maskBits, 0xff, maskPitch * height);
+
+	HDC hdc = GetDC(NULL);
+
+	LPVOID pixels;
+
+	ICONINFO ii;
+	memset(&ii, 0, sizeof(ii));
+	ii.fIcon = FALSE;
+	ii.xHotspot = (DWORD)hotSpotX;
+	ii.yHotspot = (DWORD)hotSpotY;
+	ii.hbmColor = CreateDIBSection(hdc, (BITMAPINFO*)&bmp, DIB_RGB_COLORS, &pixels, NULL, 0);
+	ii.hbmMask = CreateBitmap(width, height, 1, 1, maskBits);
+	ReleaseDC(NULL, hdc);
+
+	size_t cursorPitch = width * 4;
+
+	size_t numPixels = width * height;
+	memcpy(pixels, pixelDataRGBA, numPixels * 4);
+
+	for (size_t i = 0; i < numPixels; i++)
+	{
+		uint8_t *pixel = static_cast<uint8_t*>(pixels) + i * 4;
+		std::swap(pixel[0], pixel[2]);
+	}
+
+	HICON hicon = CreateIconIndirect(&ii);
+
+	DeleteObject(ii.hbmColor);
+	DeleteObject(ii.hbmMask);
+
+	if (!hicon)
+		return nullptr;
+
+	void *storage = malloc(sizeof(GpColorCursor_Win32));
 	if (!storage)
 	{
-		DestroyCursor(cursor);
+		DestroyIcon(hicon);
 		return nullptr;
 	}
 
-	return new (storage) GpCursor_Win32(reinterpret_cast<HCURSOR>(cursor));
+	return new (storage) GpColorCursor_Win32(reinterpret_cast<HCURSOR>(hicon));
 }
 
-GpCursor_Win32::GpCursor_Win32(HCURSOR cursor)
+GpColorCursor_Win32::GpColorCursor_Win32(HCURSOR cursor)
 	: m_cursor(cursor)
 	, m_refCount(1)
 {
 }
 
-GpCursor_Win32::~GpCursor_Win32()
+GpColorCursor_Win32::~GpColorCursor_Win32()
 {
-	DestroyCursor(m_cursor);
+	DestroyIcon(m_cursor);
 }
 
-const HCURSOR &GpCursor_Win32::GetHCursor() const
+const HCURSOR &GpColorCursor_Win32::GetHCursor() const
 {
 	return m_cursor;
 }
 
-void GpCursor_Win32::IncRef()
+void GpColorCursor_Win32::IncRef()
 {
 	m_refCount++;
 }
 
-void GpCursor_Win32::DecRef()
+void GpColorCursor_Win32::DecRef()
 {
 	m_refCount--;
 	if (m_refCount == 0)
 	{
-		this->~GpCursor_Win32();
+		this->~GpColorCursor_Win32();
 		free(this);
 	}
 }