@@ -6,6 +6,7 @@ set(CMAKE_C_FLAGS_RELEASE "-O3 -Wall -Wextra -std=gnu99")
 set(USE_CLI_DEBUGGER ON CACHE BOOL "Whether or not to enable the CLI-mode ARM debugger")
 set(USE_GDB_STUB ON CACHE BOOL "Whether or not to enable the GDB stub ARM debugger")
 set(USE_FFMPEG ON CACHE BOOL "Whether or not to enable FFmpeg support")
+set(USE_PNG ON CACHE BOOL "Whether or not to enable PNG support")
 set(BUILD_SDL ON CACHE BOOL "Build SDL frontend")
 set(BUILD_PERF ON CACHE BOOL "Build performance profiling tool")
 file(GLOB ARM_SRC ${CMAKE_SOURCE_DIR}/src/arm/*.c)
@@ -107,9 +108,12 @@ list(APPEND UTIL_SRC "${CMAKE_SOURCE_DIR}/src/platform/ffmpeg/ffmpeg-encoder.c")
 	list(APPEND DEPENDENCY_LIB ${LIBAVCODEC_LIBRARIES} ${LIBAVFORMAT_LIBRARIES} ${LIBAVUTIL_LIBRARIES})
 endif()
 
-find_package(PNG REQUIRED)
-find_package(ZLIB REQUIRED)
-list(APPEND DEPENDENCY_LIB ${PNG_LIBRARIES} ${ZLIB_LIBRARIES})
+if(USE_PNG)
+	find_package(PNG REQUIRED)
+	find_package(ZLIB REQUIRED)
+	add_definitions(-DUSE_PNG)
+	list(APPEND DEPENDENCY_LIB ${PNG_LIBRARIES} ${ZLIB_LIBRARIES})
+endif()
 
 add_library(${BINARY_NAME} SHARED ${ARM_SRC} ${GBA_SRC} ${DEBUGGER_SRC} ${RENDERER_SRC} ${UTIL_SRC} ${VFS_SRC} ${OS_SRC})
 target_link_libraries(${BINARY_NAME} m ${DEBUGGER_LIB} ${OS_LIB} ${DEPENDENCY_LIB})

@@ -7,12 +7,15 @@ #include "gba-thread.h"
 #include "gba-video.h"
 
 #include "util/memory.h"
-#include "util/png-io.h"
 #include "util/vfs.h"
 
 #include <fcntl.h>
+
+#ifdef USE_PNG
+#include "util/png-io.h"
 #include <png.h>
 #include <zlib.h>
+#endif
 
 const uint32_t GBA_SAVESTATE_MAGIC = 0x01000000;
 
@@ -113,6 +116,7 @@ }
 	return vf;
 }
 
+#ifdef USE_PNG
 static bool _savePNGState(struct GBA* gba, struct VFile* vf) {
 	unsigned stride;
 	void* pixels = 0;
@@ -168,6 +172,7 @@ gba->video.renderer->putPixels(gba->video.renderer, VIDEO_HORIZONTAL_PIXELS, pixels);
 	GBASyncPostFrame(gba->sync);
 	return true;
 }
+#endif
 
 bool GBASaveState(struct GBA* gba, struct VDir* dir, int slot, bool screenshot) {
 	struct VFile* vf = _getStateVf(gba, dir, slot, true);
@@ -198,23 +203,28 @@ return false;
 		}
 		GBASerialize(gba, state);
 		vf->unmap(vf, state, sizeof(struct GBASerializedState));
-	} else {
+		return true;
+	}
+	#ifdef USE_PNG
+	else {
 		return _savePNGState(gba, vf);
 	}
-	return true;
+	#endif
+	return false;
 }
 
 bool GBALoadStateNamed(struct GBA* gba, struct VFile* vf) {
-	if (!isPNG(vf)) {
-		struct GBASerializedState* state = vf->map(vf, sizeof(struct GBASerializedState), MAP_READ);
-		if (!state) {
-			return false;
-		}
-		GBADeserialize(gba, state);
-		vf->unmap(vf, state, sizeof(struct GBASerializedState));
-	} else {
+	#ifdef USE_PNG
+	if (isPNG(vf)) {
 		return _loadPNGState(gba, vf);
 	}
+	#endif
+	struct GBASerializedState* state = vf->map(vf, sizeof(struct GBASerializedState), MAP_READ);
+	if (!state) {
+		return false;
+	}
+	GBADeserialize(gba, state);
+	vf->unmap(vf, state, sizeof(struct GBASerializedState));
 	return true;
 }
 

@@ -520,6 +520,7 @@ return TlsGetValue(_contextKey);
 }
 #endif
 
+#ifdef USE_PNG
 void GBAThreadTakeScreenshot(struct GBAThread* threadContext) {
 	unsigned stride;
 	void* pixels = 0;
@@ -531,6 +532,7 @@ PNGWritePixels(png, VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS, stride, pixels);
 	PNGWriteClose(png, info);
 	vf->close(vf);
 }
+#endif
 
 void GBASyncPostFrame(struct GBASync* sync) {
 	if (!sync) {

@@ -112,7 +112,9 @@ void GBAThreadTogglePause(struct GBAThread* threadContext);
 void GBAThreadPauseFromThread(struct GBAThread* threadContext);
 struct GBAThread* GBAThreadGetContext(void);
 
+#ifdef USE_PNG
 void GBAThreadTakeScreenshot(struct GBAThread* threadContext);
+#endif
 
 void GBASyncPostFrame(struct GBASync* sync);
 bool GBASyncWaitFrameStart(struct GBASync* sync, int frameskip);

@@ -1,5 +1,7 @@
 #include "util/png-io.h"
 
+#ifdef USE_PNG
+
 #include "vfs.h"
 
 static void _pngWrite(png_structp png, png_bytep buffer, png_size_t size) {
@@ -177,3 +179,5 @@
 void PNGReadClose(png_structp png, png_infop info, png_infop end) {
 	png_destroy_read_struct(&png, &info, &end);
 }
+
+#endif

@@ -3,6 +3,8 @@ #define PNG_IO_H
 
 #include "common.h"
 
+#ifdef USE_PNG
+
 #include <png.h>
 
 struct VFile;
@@ -29,3 +31,5 @@ bool PNGReadFooter(png_structp png, png_infop end);
 void PNGReadClose(png_structp png, png_infop info, png_infop end);
 
 #endif
+
+#endif