GUI: Make savestate screens show the relevant savestate picture

src/gba/gui/gui-runner.c

@@ -10,6 +10,8 @@
 #include "util/gui/file-select.h"
 #include "util/gui/font.h"
 #include "util/gui/menu.h"
+#include "util/memory.h"
+#include "util/png-io.h"
 #include "util/vfs.h"
 
 enum {
@@ -30,13 +32,46 @@ enum {
 	RUNNER_STATE_9 = 0x90000,
 };
 
-static void _drawBackground(struct GUIBackground* background) {
+static void _drawBackground(struct GUIBackground* background, void* context) {
+	UNUSED(context);
 	struct GBAGUIBackground* gbaBackground = (struct GBAGUIBackground*) background;
 	if (gbaBackground->p->drawFrame) {
 		gbaBackground->p->drawFrame(gbaBackground->p, true);
 	}
 }
 
+static void _drawState(struct GUIBackground* background, void* id) {
+	struct GBAGUIBackground* gbaBackground = (struct GBAGUIBackground*) background;
+	int stateId = ((int) id) >> 16;
+	if (gbaBackground->p->drawScreenshot) {
+		struct VFile* vf = GBAGetState(gbaBackground->p->context.gba, 0, stateId, false);
+		uint32_t* pixels = anonymousMemoryMap(VIDEO_HORIZONTAL_PIXELS * VIDEO_VERTICAL_PIXELS * 4);
+		bool success = false;
+		if (vf && isPNG(vf) && pixels) {
+			png_structp png = PNGReadOpen(vf, PNG_HEADER_BYTES);
+			png_infop info = png_create_info_struct(png);
+			png_infop end = png_create_info_struct(png);
+			if (png && info && end) {
+				success = PNGReadHeader(png, info);
+				success = success && PNGReadPixels(png, info, pixels, VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS, VIDEO_HORIZONTAL_PIXELS);
+				success = success && PNGReadFooter(png, end);
+			}
+			PNGReadClose(png, info, end);
+		}
+		if (vf) {
+			vf->close(vf);
+		}
+		if (success) {
+			gbaBackground->p->drawScreenshot(gbaBackground->p, pixels, true);
+		} else if (gbaBackground->p->drawFrame) {
+			gbaBackground->p->drawFrame(gbaBackground->p, true);
+		}
+		if (pixels) {
+			mappedMemoryFree(pixels, VIDEO_HORIZONTAL_PIXELS * VIDEO_VERTICAL_PIXELS * 4);
+		}
+	}
+}
+
 static void _updateLux(struct GBALuminanceSource* lux) {
 	UNUSED(lux);
 }
@@ -72,6 +107,12 @@ void GBAGUIDeinit(struct GBAGUIRunner* runner) {
 }
 
 void GBAGUIRunloop(struct GBAGUIRunner* runner) {
+	struct GBAGUIBackground drawState = {
+		.d = {
+			.draw = _drawState
+		},
+		.p = runner
+	};
 	struct GUIMenu pauseMenu = {
 		.title = "Game Paused",
 		.index = 0,
@@ -80,12 +121,12 @@ void GBAGUIRunloop(struct GBAGUIRunner* runner) {
 	struct GUIMenu stateSaveMenu = {
 		.title = "Save state",
 		.index = 0,
-		.background = &runner->background.d
+		.background = &drawState.d
 	};
 	struct GUIMenu stateLoadMenu = {
 		.title = "Load state",
 		.index = 0,
-		.background = &runner->background.d
+		.background = &drawState.d
 	};
 	GUIMenuItemListInit(&pauseMenu.items, 0);
 	GUIMenuItemListInit(&stateSaveMenu.items, 9);

src/gba/gui/gui-runner.h

@@ -37,6 +37,7 @@ struct GBAGUIRunner {
 	void (*gameUnloaded)(struct GBAGUIRunner*);
 	void (*prepareForFrame)(struct GBAGUIRunner*);
 	void (*drawFrame)(struct GBAGUIRunner*, bool faded);
+	void (*drawScreenshot)(struct GBAGUIRunner*, const uint32_t* pixels, bool faded);
 	void (*paused)(struct GBAGUIRunner*);
 	void (*unpaused)(struct GBAGUIRunner*);
 	uint16_t (*pollGameInput)(struct GBAGUIRunner*);

src/platform/3ds/main.c

@@ -112,15 +112,39 @@ static void _gameUnloaded(struct GBAGUIRunner* runner) {
 }
 
 static void _drawFrame(struct GBAGUIRunner* runner, bool faded) {
+	UNUSED(runner);
+	GSPGPU_FlushDataCache(0, renderer.outputBuffer, 256 * VIDEO_VERTICAL_PIXELS * 2);
 	GX_SetDisplayTransfer(0, renderer.outputBuffer, GX_BUFFER_DIM(256, VIDEO_VERTICAL_PIXELS), tex->data, GX_BUFFER_DIM(256, VIDEO_VERTICAL_PIXELS), 0x000002202);
+	gspWaitForPPF();
 	GSPGPU_FlushDataCache(0, tex->data, 256 * VIDEO_VERTICAL_PIXELS * 2);
+	sf2d_draw_texture_scale_blend(tex, 40, 296, 1, -1, 0xFFFFFF3F | (faded ? 0 : 0xC0));
 #if RESAMPLE_LIBRARY == RESAMPLE_BLIP_BUF
 	if (!hasSound) {
 		blip_clear(runner->context.gba->audio.left);
 		blip_clear(runner->context.gba->audio.right);
 	}
 #endif
+}
+
+static void _drawScreenshot(struct GBAGUIRunner* runner, const uint32_t* pixels, bool faded) {
+	UNUSED(runner);
+	u16* newPixels = linearMemAlign(256 * VIDEO_VERTICAL_PIXELS * 2, 0x80);
+	unsigned y, x;
+	for (y = 0; y < VIDEO_VERTICAL_PIXELS; ++y) {
+		for (x = 0; x < VIDEO_HORIZONTAL_PIXELS; ++x) {
+			u16 pixel = (*pixels >> 19) & 0x1F;
+			pixel |= (*pixels >> 5) & 0x7C0;
+			pixel |= (*pixels << 8) & 0xF800;
+			newPixels[y * 256 + x] = pixel;
+			++pixels;
+		}
+		memset(&newPixels[y * 256 + VIDEO_HORIZONTAL_PIXELS], 0, 32);
+	}
+	GSPGPU_FlushDataCache(0, (void*) newPixels, VIDEO_HORIZONTAL_PIXELS * VIDEO_VERTICAL_PIXELS * 2);
+	GX_SetDisplayTransfer(0, (void*) newPixels, GX_BUFFER_DIM(VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS), tex->data, GX_BUFFER_DIM(256, VIDEO_VERTICAL_PIXELS), 0x000002202);
 	gspWaitForPPF();
+	linearFree(newPixels);
+	GSPGPU_FlushDataCache(0, (void*) tex->data, 256 * VIDEO_VERTICAL_PIXELS * 2);
 	sf2d_draw_texture_scale_blend(tex, 40, 296, 1, -1, 0xFFFFFF3F | (faded ? 0 : 0xC0));
 }
 
@@ -264,6 +288,7 @@ int main() {
 		.gameUnloaded = _gameUnloaded,
 		.prepareForFrame = 0,
 		.drawFrame = _drawFrame,
+		.drawScreenshot = _drawScreenshot,
 		.paused = _gameUnloaded,
 		.unpaused = _gameLoaded,
 		.pollGameInput = _pollGameInput

src/util/gui.h

@@ -29,7 +29,7 @@ enum GUIInput {
 };
 
 struct GUIBackground {
-	void (*draw)(struct GUIBackground*);
+	void (*draw)(struct GUIBackground*, void* context);
 };
 
 struct GUIParams {

src/util/gui/menu.c

@@ -71,7 +71,7 @@ enum GUIMenuExitReason GUIShowMenu(struct GUIParams* params, struct GUIMenu* men
 
 		params->drawStart();
 		if (menu->background) {
-			menu->background->draw(menu->background);
+			menu->background->draw(menu->background, GUIMenuItemListGetPointer(&menu->items, menu->index)->data);
 		}
 		if (params->guiPrepare) {
 			params->guiPrepare();