add loading of g1.dat

src/addresses.h

@@ -69,6 +69,8 @@
 #define RCT2_ADDRESS_PLACE_OBJECT_MODIFIER			0x009DEA70
 #define RCT2_ADDRESS_ON_TUTORIAL					0x009DEA71
 
+#define RCT2_ADDRESS_G1_ELEMENTS					0x009EBD28
+
 #define RCT2_ADDRESS_SPRITE_LIST					0x010E63BC
 #define RCT2_ADDRESS_SPRITES_NEXT_INDEX				0x013573BC
 #define RCT2_ADDRESS_SPRITES_START_VEHICLE			0x013573BE
@@ -113,23 +115,47 @@ static void RCT2_CALLFUNC_X(int address, int *_eax, int *_ebx, int *_ecx, int *_
 	__asm {
 		push ebp
 		push address
+
+		// Set register to variable address, then set register to variable value
 		mov eax, [_eax]
+		mov eax, [eax]
 		mov ebx, [_ebx]
+		mov ebx, [ebx]
 		mov ecx, [_ecx]
+		mov ecx, [ecx]
 		mov edx, [_edx]
+		mov edx, [edx]
 		mov esi, [_esi]
+		mov esi, [esi]
 		mov edi, [_edi]
+		mov edi, [edi]
 		mov ebp, [_ebp]
+		mov ebp, [ebp]
+
+		// Call func address
 		call[esp]
 		add esp, 4
 		pop ebp
+
 		// mov[_ebp], ebp
-		mov[_edi], edi
-		mov[_esi], esi
-		mov[_edx], edx
-		mov[_ecx], ecx
-		mov[_ebx], ebx
-		mov [_eax], eax		
+
+		// Get resulting ebx, ecx, edx, esi, edi registers
+		push eax
+		mov eax, [_edi]
+		mov [eax], edi
+		mov eax, [_esi]
+		mov [eax], esi
+		mov eax, [_edx]
+		mov [eax], edx
+		mov eax, [_ecx]
+		mov [eax], ecx
+		mov eax, [_ebx]
+		mov [eax], ebx
+		pop eax
+
+		// Get resulting eax register
+		mov ebx, [_eax]
+		mov [ebx], eax
 	}
 }
 

src/gfx.c

@@ -18,10 +18,52 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *****************************************************************************/
 
+#include <assert.h>
+#include <stdio.h>
+#include <windows.h>
 #include "addresses.h"
 #include "gfx.h"
 #include "rct2.h"
 
+/**
+ * 
+ *  rct2: 0x00678998
+ */
+void gfx_load_g1()
+{
+	HANDLE hFile;
+	DWORD bytesRead;
+	DWORD header[2];
+
+	int i;
+	int g1BufferSize;
+	void* g1Buffer;
+
+	rct_g1_element *g1Elements = RCT2_ADDRESS(RCT2_ADDRESS_G1_ELEMENTS, rct_g1_element);
+
+	hFile = CreateFile(get_file_path(PATH_ID_G1), GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING,
+		FILE_FLAG_RANDOM_ACCESS | FILE_ATTRIBUTE_NORMAL, NULL);
+	if (hFile != INVALID_HANDLE_VALUE) {
+		ReadFile(hFile, header, 8, &bytesRead, NULL);
+		if (bytesRead == 8) {
+			g1BufferSize = header[1];
+			g1Buffer = rct2_malloc(g1BufferSize);
+			ReadFile(hFile, g1Elements, 29294 * sizeof(rct_g1_element), &bytesRead, NULL);
+			ReadFile(hFile, g1Buffer, g1BufferSize, &bytesRead, NULL);
+			CloseHandle(hFile);
+
+			for (i = 0; i < 29294; i++)
+				g1Elements[i].offset += (int)g1Buffer;
+
+			return;
+		}
+	}
+
+	// exit with error
+	fprintf(stderr, "Unable to load g1.dat");
+	assert(0);
+}
+
 /**
  * Clears the screen with the specified colour.
  *  rct2: 0x00678A9F

src/gfx.h

@@ -21,6 +21,9 @@
 #ifndef _GFX_H_
 #define _GFX_H_
 
+#include "rct2.h"
+
+// Size: 0x10
 typedef struct {
 	char* bits;			// 0x00
 	short x;			// 0x04
@@ -32,6 +35,19 @@ typedef struct {
 	char var_0F;		// 0x0F
 } rct_drawpixelinfo;
 
+// Size: 0x10
+typedef struct {
+	uint8* offset;			// 0x00
+	sint16 width;			// 0x04
+	sint16 height;			// 0x06
+	sint16 x_offset;		// 0x08
+	sint16 y_offset;		// 0x0A
+	uint16 flags;			// 0x0C
+	sint16 unused;			// 0x0E
+} rct_g1_element;
+
+void gfx_load_g1();
+
 void gfx_clear(rct_drawpixelinfo *dpi, int colour);
 void gfx_fill_rect(rct_drawpixelinfo *dpi, int left, int top, int right, int bottom, int colour);
 void gfx_draw_sprite(rct_drawpixelinfo *dpi, int image_id, int x, int y);

src/rct2.c

@@ -100,7 +100,7 @@ void rct2_init()
 	RCT2_CALLPROC_EBPSAFE(0x006A8B40); // object_load_list()
 	RCT2_CALLPROC_EBPSAFE(0x006775A8); // scenario_load_list()
 	RCT2_CALLPROC_X(0x006CED50, 0, 0, 0, 253, 0, 0, 0); // track_load_list(253)
-	RCT2_CALLPROC_EBPSAFE(0x00678998); // gfx_load_g1()
+	gfx_load_g1();
 	RCT2_CALLPROC_EBPSAFE(0x006C19AC);
 	osinterface_init();
 	RCT2_CALLPROC_EBPSAFE(0x006BA8E0); // init_audio();
@@ -205,4 +205,26 @@ void rct2_update_2()
 		title_update();
 	else
 		game_update();
+}
+
+/**
+ * 
+ *  rct2: 0x00674E6C
+ */
+char *get_file_path(int pathId)
+{
+	int eax, ebx, ecx, edx, esi, edi, ebp;
+
+	ebx = pathId;
+	RCT2_CALLFUNC_X(0x00674E6C, &eax, &ebx, &ecx, &edx, &esi, &edi, &ebp);
+	return ebx;
+}
+
+/**
+ * 
+ *  rct2: 0x004068B2
+ */
+void *rct2_malloc(size_t numBytes)
+{
+	return RCT2_CALLFUNC_1(0x004068B2, void*, size_t, numBytes);
 }

src/rct2.h

@@ -21,9 +21,7 @@
 #ifndef _SDL_RCT2_H_
 #define _SDL_RCT2_H_
 
-#ifndef NULL
-	#define NULL 0
-#endif
+#include <stddef.h>
 
 typedef signed char sint8;
 typedef signed short sint16;
@@ -44,4 +42,16 @@ enum {
 	SCREEN_FLAGS_TRACK_MANAGER = 8,
 };
 
+enum {
+	PATH_ID_G1,
+	PATH_ID_PLUGIN,
+	PATH_ID_CSS1,
+	PATH_ID_CSS2,
+	PATH_ID_CSS4,
+	PATH_ID_CSS5
+};
+
+char *get_file_path(int pathId);
+void *rct2_malloc(size_t numBytes);
+
 #endif