vulkan: Add pixel-formats to query format properties

We need a database of pixel format properties to remove hardcoded magic
numbers. This commit creates a simple function to query the bytes per
pixel for common RGBA formats.

This should be promoted to or superseeded by a common spa namespaced
version.

spa/plugins/vulkan/meson.build

@@ -1,5 +1,6 @@
 spa_vulkan_sources = [
   'plugin.c',
+  'pixel-formats.c',
   'vulkan-compute-filter.c',
   'vulkan-compute-source.c',
   'vulkan-compute-utils.c',

spa/plugins/vulkan/pixel-formats.c

@@ -0,0 +1,33 @@
+/* Spa */
+/* SPDX-FileCopyrightText: Copyright © 2023 columbarius */
+/* SPDX-License-Identifier: MIT */
+
+#include "pixel-formats.h"
+
+#include <spa/utils/defs.h>
+#include <spa/param/video/raw.h>
+
+struct pixel_info {
+	uint32_t format;
+	uint32_t bpp;
+} pixel_infos[] = {
+	{ SPA_VIDEO_FORMAT_RGBA_F32, 16 },
+	{ SPA_VIDEO_FORMAT_BGRA, 4 },
+	{ SPA_VIDEO_FORMAT_RGBA, 4 },
+	{ SPA_VIDEO_FORMAT_BGRx, 4 },
+	{ SPA_VIDEO_FORMAT_RGBx, 4 },
+	{ SPA_VIDEO_FORMAT_BGR, 3 },
+	{ SPA_VIDEO_FORMAT_RGB, 3 },
+};
+
+bool get_pixel_format_info(uint32_t format, struct pixel_format_info *info)
+{
+	struct pixel_info *p;
+	SPA_FOR_EACH_ELEMENT(pixel_infos, p) {
+		if (p->format != format)
+			continue;
+		info->bpp = p->bpp;
+		return true;
+	}
+	return false;
+}

spa/plugins/vulkan/pixel-formats.h

@@ -0,0 +1,12 @@
+/* Spa */
+/* SPDX-FileCopyrightText: Copyright © 2023 columbarius */
+/* SPDX-License-Identifier: MIT */
+
+#include <stdint.h>
+#include <stdbool.h>
+
+struct pixel_format_info {
+	uint32_t bpp;	// bytes per pixel
+};
+
+bool get_pixel_format_info(uint32_t format, struct pixel_format_info *info);

spa/plugins/vulkan/vulkan-compute-utils.c

@@ -28,6 +28,7 @@
 #include "vulkan-compute-utils.h"
 #include "vulkan-utils.h"
 #include "utils.h"
+#include "pixel-formats.h"
 
 #define VULKAN_INSTANCE_FUNCTION(name)						\
 	PFN_##name name = (PFN_##name)vkGetInstanceProcAddr(s->base.instance, #name)
@@ -247,13 +248,16 @@ static int runExportSHMBuffers(struct vulkan_compute_state *s) {
 		if (p->direction == SPA_DIRECTION_INPUT)
 			continue;
 
+		struct pixel_format_info pixel_info;
+		CHECK(get_pixel_format_info(p->format, &pixel_info));
+
 		if (p->spa_buffers[p->current_buffer_id]->datas[0].type == SPA_DATA_MemPtr) {
 			struct spa_buffer *spa_buf = p->spa_buffers[p->current_buffer_id];
 			struct vulkan_read_pixels_info readInfo = {
 				.data = spa_buf->datas[0].data,
 				.offset = spa_buf->datas[0].chunk->offset,
 				.stride = spa_buf->datas[0].chunk->stride,
-				.bytes_per_pixel = 16,
+				.bytes_per_pixel = pixel_info.bpp,
 				.size.width = s->constants.width,
 				.size.height = s->constants.height,
 			};
@@ -479,6 +483,7 @@ int spa_vulkan_compute_use_buffers(struct vulkan_compute_state *s, struct vulkan
 
 	vulkan_wait_idle(&s->base);
 	clear_buffers(s, p);
+	p->format = SPA_VIDEO_FORMAT_UNKNOWN;
 
 	bool alloc = flags & SPA_NODE_BUFFERS_FLAG_ALLOC;
 	int ret;
@@ -544,6 +549,7 @@ int spa_vulkan_compute_use_buffers(struct vulkan_compute_state *s, struct vulkan
 		p->spa_buffers[i] = buffers[i];
 		p->n_buffers++;
 	}
+	p->format = dsp_info->format;
 
 	return 0;
 }

spa/plugins/vulkan/vulkan-compute-utils.h

@@ -33,6 +33,8 @@ struct vulkan_stream {
 	uint32_t busy_buffer_id;
 	uint32_t ready_buffer_id;
 
+	uint32_t format;
+
 	struct vulkan_buffer buffers[MAX_BUFFERS];
 	struct spa_buffer *spa_buffers[MAX_BUFFERS];
 	uint32_t n_buffers;

spa/plugins/vulkan/vulkan-utils.c

@@ -248,13 +248,13 @@ int vulkan_read_pixels(struct vulkan_base *s, struct vulkan_read_pixels_info *in
 
 	const char *d = (const char *)v + img_sub_layout.offset;
 	unsigned char *p = (unsigned char *)info->data + info->offset;
-	uint32_t bytes_per_pixel = 16;
 	uint32_t pack_stride = img_sub_layout.rowPitch;
+	spa_log_trace_fp(s->log, "Read pixels: %p to %p, stride: %d, width %d, height %d, offset %d, pack_stride %d", d, p, info->stride, info->size.width, info->size.height, info->offset, pack_stride);
 	if (pack_stride == info->stride) {
 		memcpy(p, d, info->stride * info->size.height);
 	} else {
 		for (uint32_t i = 0; i < info->size.height; i++) {
-			memcpy(p + i * info->stride, d + i * pack_stride, info->size.width * bytes_per_pixel);
+			memcpy(p + i * info->stride, d + i * pack_stride, info->size.width * info->bytes_per_pixel);
 		}
 	}
 	vkUnmapMemory(s->device, vk_buf->memory);