cam: sdl_sink: Support multi-planar formats

In order to prepare for NV12 support, implement support for multi-planar
formats in the SDL sink. This mainly consists in passing a vector of
plane data to the SDLTexture::update() function instead of a single
value.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Reviewed-by: Eric Curtin <ecurtin@redhat.com>
Tested-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

src/cam/sdl_sink.cpp

@@ -185,16 +185,23 @@ void SDLSink::renderBuffer(FrameBuffer *buffer)
 {
 	Image *image = mappedBuffers_[buffer].get();
 
-	/* \todo Implement support for multi-planar formats. */
+	std::vector<Span<const uint8_t>> planes;
-	const FrameMetadata::Plane &meta = buffer->metadata().planes()[0];
+	unsigned int i = 0;
 
-	Span<uint8_t> data = image->data(0);
+	planes.reserve(buffer->metadata()->planes().size());
+
+	for (const FrameMetadata::Plane &meta : buffer->metadata().planes()) {
+		Span<uint8_t> data = image->data(i);
 		if (meta.bytesused > data.size())
 			std::cerr << "payload size " << meta.bytesused
 				  << " larger than plane size " << data.size()
 				  << std::endl;
 
-	texture_->update(data);
+		planes.push_back(data);
+		i++;
+	}
+
+	texture_->update(planes);
 
 	SDL_RenderClear(renderer_);
 	SDL_RenderCopy(renderer_, texture_->get(), nullptr, nullptr);

src/cam/sdl_texture.h

@@ -7,6 +7,8 @@
 
 #pragma once
 
+#include <vector>
+
 #include <SDL2/SDL.h>
 
 #include "image.h"
@@ -17,7 +19,7 @@ public:
 	SDLTexture(const SDL_Rect &rect, uint32_t pixelFormat, const int pitch);
 	virtual ~SDLTexture();
 	int create(SDL_Renderer *renderer);
-	virtual void update(libcamera::Span<const uint8_t> data) = 0;
+	virtual void update(const std::vector<libcamera::Span<const uint8_t>> &data) = 0;
 	SDL_Texture *get() const { return ptr_; }
 
 protected:

src/cam/sdl_texture_mjpg.cpp

@@ -76,8 +76,8 @@ int SDLTextureMJPG::decompress(Span<const uint8_t> data)
 	return 0;
 }
 
-void SDLTextureMJPG::update(Span<const uint8_t> data)
+void SDLTextureMJPG::update(const std::vector<libcamera::Span<const uint8_t>> &data)
 {
-	decompress(data);
+	decompress(data[0]);
 	SDL_UpdateTexture(ptr_, nullptr, rgb_.get(), pitch_);
 }

src/cam/sdl_texture_mjpg.h

@@ -14,7 +14,7 @@ class SDLTextureMJPG : public SDLTexture
 public:
 	SDLTextureMJPG(const SDL_Rect &rect);
 
-	void update(libcamera::Span<const uint8_t> data) override;
+	void update(const std::vector<libcamera::Span<const uint8_t>> &data) override;
 
 private:
 	int decompress(libcamera::Span<const uint8_t> data);

src/cam/sdl_texture_yuv.cpp

@@ -14,7 +14,7 @@ SDLTextureYUYV::SDLTextureYUYV(const SDL_Rect &rect, unsigned int stride)
 {
 }
 
-void SDLTextureYUYV::update(Span<const uint8_t> data)
+void SDLTextureYUYV::update(const std::vector<libcamera::Span<const uint8_t>> &data)
 {
-	SDL_UpdateTexture(ptr_, &rect_, data.data(), pitch_);
+	SDL_UpdateTexture(ptr_, &rect_, data[0].data(), pitch_);
 }

src/cam/sdl_texture_yuv.h

@@ -13,5 +13,5 @@ class SDLTextureYUYV : public SDLTexture
 {
 public:
 	SDLTextureYUYV(const SDL_Rect &rect, unsigned int stride);
-	void update(libcamera::Span<const uint8_t> data) override;
+	void update(const std::vector<libcamera::Span<const uint8_t>> &data) override;
 };