BGE: Save screenshots in a different thread

This patch allows the game engine to keep running while performing things like PNG compression and disk I/O.

As an example, my crowd simulation rasterizer saves a screenshot for every frame. This now takes up 13 msec per frame, which was 31 msec before this patch. Effectively, it allows the simulation to save every frame and still run at 60 FPS.

Reviewers: lordloki, moguri, panzergame

Reviewed By: moguri, panzergame

Projects: #game_engine

Differential Revision: https://developer.blender.org/D1507

1 files changed, 9 insertions, 41 deletions

diff --git a/source/gameengine/GamePlayer/common/GPC_Canvas.cpp b/source/gameengine/GamePlayer/common/GPC_Canvas.cpp
index 52c4d13c638..2b355407d46 100644
--- a/source/gameengine/GamePlayer/common/GPC_Canvas.cpp
+++ b/source/gameengine/GamePlayer/common/GPC_Canvas.cpp
@@ -30,31 +30,14 @@
  */
 
 
-#ifndef NOPNG
-#ifdef WIN32
-#include "png.h"
-#else
-#include <png.h>
-#endif
-#endif // NOPNG
-
 #include "RAS_IPolygonMaterial.h"
 #include "GPC_Canvas.h"
 
-#include "BLI_path_util.h"
-#include "BLI_string.h"
-
 #include "DNA_scene_types.h"
 #include "DNA_space_types.h"
 
-#include "BKE_global.h"
-#include "BKE_main.h"
 #include "BKE_image.h"
-
-extern "C" {
-#include "IMB_imbuf.h"
-#include "IMB_imbuf_types.h"
-}
+#include "MEM_guardedalloc.h"
 
 
 GPC_Canvas::GPC_Canvas(
@@ -164,37 +147,22 @@ MakeScreenShot(
 	const char* filename
 ) {
 	// copy image data
-	unsigned char *pixels = new unsigned char[GetWidth() * GetHeight() * 4];
+	unsigned int dumpsx = GetWidth();
+	unsigned int dumpsy = GetHeight();
+	unsigned int *pixels = (unsigned int *)MEM_mallocN(sizeof(int) * dumpsx * dumpsy, "pixels");
 
 	if (!pixels) {
 		std::cout << "Cannot allocate pixels array" << std::endl;
 		return;
 	}
 
-	glReadPixels(0, 0, GetWidth(), GetHeight(), GL_RGBA, GL_UNSIGNED_BYTE, pixels);
+	glReadPixels(0, 0, dumpsx, dumpsy, GL_RGBA, GL_UNSIGNED_BYTE, pixels);
 
 	// initialize image file format data
-	ImageFormatData im_format;
-	BKE_imformat_defaults(&im_format);
-
-	// create file path 
-	char path[FILE_MAX];
-	BLI_strncpy(path, filename, sizeof(path));
-	BLI_path_abs(path, G.main->name);
-	BLI_path_frame(path, m_frame, 0);
-	m_frame++;
-	BKE_image_path_ensure_ext_from_imtype(path, im_format.imtype);
-
-	// create and save imbuf 
-	ImBuf *ibuf = IMB_allocImBuf(GetWidth(), GetHeight(), 24, 0);
-	ibuf->rect = (unsigned int*)pixels;
-
-	BKE_imbuf_write_as(ibuf, path, &im_format, false);
-
-	ibuf->rect = NULL;
-	IMB_freeImBuf(ibuf);
+	ImageFormatData *im_format = (ImageFormatData *)MEM_mallocN(sizeof(ImageFormatData), "im_format");
+	BKE_imformat_defaults(im_format);
 
-	// clean up
-	delete [] (pixels);
+	/* save_screenshot() frees dumprect and im_format */
+	save_screenshot(filename, dumpsx, dumpsy, pixels, im_format);
 }