framebuffer: Support partial flushing

Signed-off-by: Noralf Trønnes <noralf@tronnes.org>

2 files changed, 12 insertions, 0 deletions

diff --git a/kms++/inc/kms++/framebuffer.h b/kms++/inc/kms++/framebuffer.h
index 6f77b98..1bd477c 100644
--- a/kms++/inc/kms++/framebuffer.h
+++ b/kms++/inc/kms++/framebuffer.h
@@ -41,6 +41,7 @@ public:
 	uint32_t width() const override { return m_width; }
 	uint32_t height() const override { return m_height; }
 
+	void flush(uint32_t x, uint32_t y, uint32_t width, uint32_t height);
 	void flush();
 
 protected:
diff --git a/kms++/src/framebuffer.cpp b/kms++/src/framebuffer.cpp
index f1cba3b..72e1a73 100644
--- a/kms++/src/framebuffer.cpp
+++ b/kms++/src/framebuffer.cpp
@@ -34,6 +34,17 @@ Framebuffer::Framebuffer(Card& card, uint32_t id)
 	card.m_framebuffers.push_back(this);
 }
 
+void Framebuffer::flush(uint32_t x, uint32_t y, uint32_t width, uint32_t height)
+{
+	drmModeClip clip{};
+	clip.x1 = x;
+	clip.y1 = y;
+	clip.x2 = x + width;
+	clip.y2 = y + height;
+
+	drmModeDirtyFB(card().fd(), id(), &clip, 1);
+}
+
 void Framebuffer::flush()
 {
 	drmModeClip clip{};