diff --git a/LEGO1/mxbitmap.cpp b/LEGO1/mxbitmap.cpp
index 8f33fc22..1128fded 100644
--- a/LEGO1/mxbitmap.cpp
+++ b/LEGO1/mxbitmap.cpp
@@ -369,7 +369,7 @@ MxResult MxBitmap::SetBitDepth(MxBool p_isHighColor)
MxResult MxBitmap::StretchBits(HDC p_hdc, MxS32 p_xSrc, MxS32 p_ySrc, MxS32 p_xDest, MxS32 p_yDest, MxS32 p_destWidth, MxS32 p_destHeight)
{
// Compression fix?
- if ((this->m_bmiHeader->biCompression != 16) && (0 < this->m_bmiHeader->biHeight)) {
+ if ((this->m_bmiHeader->biCompression != BI_RGB_TOPDOWN) && (0 < this->m_bmiHeader->biHeight)) {
p_ySrc = (this->m_bmiHeader->biHeight - p_destHeight) - p_ySrc;
}
diff --git a/LEGO1/mxbitmap.h b/LEGO1/mxbitmap.h
index 53b01e16..6bb1c5fd 100644
--- a/LEGO1/mxbitmap.h
+++ b/LEGO1/mxbitmap.h
@@ -21,6 +21,13 @@ struct MxBITMAPINFO {
RGBQUAD bmiColors[256];
};
+// Non-standard value for biCompression in the BITMAPINFOHEADER struct.
+// By default, uncompressed bitmaps (BI_RGB) are stored in bottom-up order.
+// You can specify that the bitmap has top-down order instead by providing
+// a negative number for biHeight. It could be that Mindscape decided on a
+// belt & suspenders approach here.
+#define BI_RGB_TOPDOWN 0x10
+
// SIZE 0x20
// VTABLE 0x100dc7b0
class MxBitmap : public MxCore
@@ -43,6 +50,10 @@ public:
virtual MxResult StretchBits(HDC p_hdc, MxS32 p_xSrc, MxS32 p_ySrc, MxS32 p_xDest, MxS32 p_yDest, MxS32 p_destWidth, MxS32 p_destHeight); // vtable+40
inline BITMAPINFOHEADER *GetBmiHeader() const { return m_bmiHeader; }
+ inline MxLong GetBmiWidth() const { return m_bmiHeader->biWidth; }
+ inline MxLong GetBmiHeight() const { return m_bmiHeader->biHeight; }
+ inline MxLong GetBmiHeightAbs() const { return m_bmiHeader->biHeight > 0 ? m_bmiHeader->biHeight : -m_bmiHeader->biHeight; }
+ inline MxU8 *GetBitmapData() const { return m_data; }
private:
MxResult ImportColorsToPalette(RGBQUAD*, MxPalette*);
diff --git a/LEGO1/mxvideopresenter.cpp b/LEGO1/mxvideopresenter.cpp
index a22adcd4..5abef00d 100644
--- a/LEGO1/mxvideopresenter.cpp
+++ b/LEGO1/mxvideopresenter.cpp
@@ -2,7 +2,7 @@
#include "MxVideoManager.h"
DECOMP_SIZE_ASSERT(MxVideoPresenter, 0x64);
-DECOMP_SIZE_ASSERT(MxVideoPresenter::UnkStruct, 0xc);
+DECOMP_SIZE_ASSERT(MxVideoPresenter::AlphaMask, 0xc);
// OFFSET: LEGO1 0x1000c700
void MxVideoPresenter::VTable0x5c(undefined4 p_unknown1)
@@ -49,28 +49,116 @@ LPDIRECTDRAWSURFACE MxVideoPresenter::VTable0x78()
// OFFSET: LEGO1 0x1000c7c0
MxBool MxVideoPresenter::VTable0x7c()
{
- return (m_bitmap != NULL) || (m_unk54 != NULL);
+ return (m_bitmap != NULL) || (m_alpha != NULL);
}
// OFFSET: LEGO1 0x1000c7e0
MxS32 MxVideoPresenter::GetWidth()
{
- return m_unk54 ? m_unk54->width
+ return m_alpha ? m_alpha->m_width
: m_bitmap->GetBmiHeader()->biWidth;
}
// OFFSET: LEGO1 0x1000c800
MxS32 MxVideoPresenter::GetHeight()
{
- return m_unk54 ? m_unk54->height
+ return m_alpha ? m_alpha->m_height
: m_bitmap->GetBmiHeader()->biHeight;
}
+// OFFSET: LEGO1 0x100b24f0
+MxVideoPresenter::AlphaMask::AlphaMask(MxBitmap &p_bitmap)
+{
+ m_width = p_bitmap.GetBmiWidth();
+ // DECOMP: ECX becomes word-sized if these are not two separate actions.
+ MxLong _height = p_bitmap.GetBmiHeightAbs();
+ m_height = _height;
+
+ MxS32 size = ((m_width * m_height) / 8) + 1;
+ m_bitmask = new MxU8[size];
+ memset(m_bitmask, 0, size);
+
+ MxU32 biCompression = p_bitmap.GetBmiHeader()->biCompression;
+ MxU32 rows_before_top;
+ MxU8 *bitmap_src_ptr;
+
+ // The goal here is to enable us to walk through the bitmap's rows
+ // in order, regardless of the orientation. We want to end up at the
+ // start of the first row, which is either at position 0, or at
+ // (image_stride * biHeight) - 1.
+
+ // Reminder: Negative biHeight means this is a top-down DIB.
+ // Otherwise it is bottom-up.
+
+ if (biCompression == BI_RGB) {
+ // DECOMP: I think this must be an OR. If not, the check for
+ // biCompression == 16 gets optimized away.
+ if (biCompression == BI_RGB_TOPDOWN || p_bitmap.GetBmiHeight() < 0) {
+ rows_before_top = 0;
+ } else {
+ rows_before_top = p_bitmap.GetBmiHeightAbs();
+ rows_before_top--;
+ }
+
+ goto seek_to_last_row;
+ } else if (biCompression == BI_RGB_TOPDOWN) {
+ // DECOMP: This is the only condition where we skip the
+ // calculation below.
+ bitmap_src_ptr = p_bitmap.GetBitmapData();
+ } else {
+ if (p_bitmap.GetBmiHeight() < 0) {
+ rows_before_top = 0;
+ } else {
+ rows_before_top = p_bitmap.GetBmiHeightAbs();
+ rows_before_top--;
+ }
+
+// TODO: would prefer not to use goto if we can figure this structure out
+seek_to_last_row:
+ bitmap_src_ptr = ((p_bitmap.GetBmiWidth()+3)&-4) * rows_before_top + p_bitmap.GetBitmapData();
+ }
+
+ // How many bytes are there for each row of the bitmap?
+ // (i.e. the image stride)
+ // If this is a bottom-up DIB, we will walk it in reverse.
+ // TODO: Same rounding trick as in MxBitmap
+ MxS32 row_seek = ((m_height+3)&-4);
+ if (p_bitmap.GetBmiHeight() < 0)
+ row_seek = -row_seek;
+
+ // The actual offset into the m_bitmask array. The two for-loops
+ // are just for counting the pixels.
+ MxS32 offset = 0;
+
+ MxU8 *t_ptr = bitmap_src_ptr;
+ for (MxS32 j = 0; j < m_height; j++) {
+ for (MxS32 i = 0; i < m_width; i++) {
+ if (*t_ptr) {
+ // TODO: Second CDQ instruction for abs() should not be there.
+ MxU32 shift = abs(offset) & 7;
+ m_bitmask[offset / 8] |= (1 << abs(shift));
+ }
+ t_ptr++;
+ offset++;
+ }
+ // Seek to the start of the next row
+ bitmap_src_ptr += row_seek;
+ t_ptr = bitmap_src_ptr;
+ }
+}
+
+// OFFSET: LEGO1 0x100b26d0
+MxVideoPresenter::AlphaMask::~AlphaMask()
+{
+ if (m_bitmask)
+ delete[] m_bitmask;
+}
+
// OFFSET: LEGO1 0x100b2760
void MxVideoPresenter::Init()
{
m_bitmap = NULL;
- m_unk54 = NULL;
+ m_alpha = NULL;
m_unk5c = 1;
m_unk58 = NULL;
m_unk60 = -1;
@@ -99,7 +187,7 @@ void MxVideoPresenter::Destroy(MxBool p_fromDestructor)
m_flags = m_flags & 0xfb;
}
- if (MVideoManager() && (m_unk54 || m_bitmap)) {
+ if (MVideoManager() && (m_alpha || m_bitmap)) {
MxS32 height = GetHeight();
MxS32 width = GetWidth();
@@ -112,7 +200,7 @@ void MxVideoPresenter::Destroy(MxBool p_fromDestructor)
}
delete m_bitmap;
- delete m_unk54;
+ delete m_alpha;
Init();
diff --git a/LEGO1/mxvideopresenter.h b/LEGO1/mxvideopresenter.h
index 30a6ada7..4f66075c 100644
--- a/LEGO1/mxvideopresenter.h
+++ b/LEGO1/mxvideopresenter.h
@@ -49,16 +49,18 @@ public:
// TODO: Not sure what this is. Seems to have size of 12 bytes
// based on 0x100b9e9a. Values are copied from the bitmap header.
- struct UnkStruct {
- undefined unk0[4];
- MxU16 width;
- MxU16 height;
+ // SIZE 0xc
+ struct AlphaMask {
+ MxU8 *m_bitmask;
+ MxU16 m_width;
+ MxU16 m_height;
- virtual ~UnkStruct() {}
+ AlphaMask(MxBitmap &);
+ virtual ~AlphaMask();
};
MxBitmap *m_bitmap;
- UnkStruct *m_unk54;
+ AlphaMask *m_alpha;
LPDIRECTDRAWSURFACE m_unk58;
undefined2 m_unk5c;
unsigned char m_flags; // 0x5e