VIDEO/GOB: Add CoktelDecoder::getDirtyRects()

This allows for the client code to only update the parts of the
video frames that actually changed.

svn-id: r51859

2 files changed, 17 insertions, 9 deletions

diff --git a/graphics/video/coktel_decoder.cpp b/graphics/video/coktel_decoder.cpp
index 6f846c9a07..a9a2e157a3 100644
--- a/graphics/video/coktel_decoder.cpp
+++ b/graphics/video/coktel_decoder.cpp
@@ -29,7 +29,7 @@
 
 namespace Graphics {
 
-CoktelDecoder::State::State() : left(0), top(0), right(0), bottom(0), flags(0), speechId(0) {
+CoktelDecoder::State::State() : flags(0), speechId(0) {
 }
 
 
@@ -97,6 +97,10 @@ void CoktelDecoder::setXY(uint16 x, uint16 y) {
 	_y = y;
 }
 
+const Common::List<Common::Rect> &CoktelDecoder::getDirtyRects() const {
+	return _dirtyRects;
+}
+
 void CoktelDecoder::close() {
 	freeSurface();
 
@@ -299,6 +303,8 @@ void PreIMDDecoder::processFrame() {
 }
 
 void PreIMDDecoder::renderFrame() {
+	_dirtyRects.clear();
+
 	uint16 w = CLIP<int32>(_surface.w - _x, 0, _width);
 	uint16 h = CLIP<int32>(_surface.h - _y, 0, _height);
 
@@ -317,6 +323,8 @@ void PreIMDDecoder::renderFrame() {
 
 		frameDataSize -= n;
 	}
+
+	_dirtyRects.push_back(Common::Rect(_x, _y, _x + _width, _y + _height));
 }
 
 PixelFormat PreIMDDecoder::getPixelFormat() const {
diff --git a/graphics/video/coktel_decoder.h b/graphics/video/coktel_decoder.h
index a4d12c5294..ea405974d6 100644
--- a/graphics/video/coktel_decoder.h
+++ b/graphics/video/coktel_decoder.h
@@ -33,6 +33,9 @@
 #ifndef GRAPHICS_VIDEO_COKTELDECODER_H
 #define GRAPHICS_VIDEO_COKTELDECODER_H
 
+#include "common/list.h"
+#include "common/rect.h"
+
 #include "graphics/video/video_decoder.h"
 
 #include "sound/mixer.h"
@@ -42,14 +45,6 @@ namespace Graphics {
 class CoktelDecoder : public FixedRateVideoDecoder {
 public:
 	struct State {
-		/** Left-most value of the updated rectangle. */
-		int16 left;
-		/** Top-most value of the updated rectangle. */
-		int16 top;
-		/** Right-most value of the updated rectangle. */
-		int16 right;
-		/** Bottom-most value of the updated rectangle. */
-		int16 bottom;
 		/** Set accordingly to what was done. */
 		uint32 flags;
 		/** The id of the spoken words. */
@@ -72,6 +67,9 @@ public:
 	/** Draw the video starting at this position within the video memory. */
 	void setXY(uint16 x, uint16 y);
 
+	/** Return a list of rectangles that changed in the last frame. */
+	const Common::List<Common::Rect> &getDirtyRects() const;
+
 	// VideoDecoder interface
 
 	void close();
@@ -102,6 +100,8 @@ protected:
 	bool    _ownSurface;
 	Surface _surface;
 
+	Common::List<Common::Rect> _dirtyRects;
+
 	Common::Rational _frameRate;
 
 	bool hasSurface();