Method texture_get_data

servers/rendering/rendering_device.cpp:2024–2141

}

Vector<uint8_t> RenderingDevice::texture_get_data(RID p_texture, uint32_t p_layer) {
	ERR_RENDER_THREAD_GUARD_V(Vector<uint8_t>());

	Texture *tex = texture_owner.get_or_null(p_texture);
	ERR_FAIL_NULL_V(tex, Vector<uint8_t>());

	ERR_FAIL_COND_V_MSG(tex->bound, Vector<uint8_t>(),
			"Texture can't be retrieved while a draw list that uses it as part of a framebuffer is being created. Ensure the draw list is finalized (and that the color/depth texture using it is not set to `RenderingDevice.FINAL_ACTION_CONTINUE`) to retrieve this texture.");
	ERR_FAIL_COND_V_MSG(!(tex->usage_flags & TEXTURE_USAGE_CAN_COPY_FROM_BIT), Vector<uint8_t>(),
			"Texture requires the `RenderingDevice.TEXTURE_USAGE_CAN_COPY_FROM_BIT` to be set to be retrieved.");

	ERR_FAIL_COND_V(p_layer >= tex->layers, Vector<uint8_t>());

	// Clear the texture if the driver requires it during its first use.
	_texture_check_pending_clear(p_texture, tex);

	_check_transfer_worker_texture(tex);

	if (tex->usage_flags & TEXTURE_USAGE_CPU_READ_BIT) {
		// Does not need anything fancy, map and read.
		return _texture_get_data(tex, p_layer);
	} else {
		LocalVector<RDD::TextureCopyableLayout> mip_layouts;
		uint32_t work_mip_alignment = driver->api_trait_get(RDD::API_TRAIT_TEXTURE_TRANSFER_ALIGNMENT);
		uint32_t work_buffer_size = 0;
		mip_layouts.resize(tex->mipmaps);
		for (uint32_t i = 0; i < tex->mipmaps; i++) {
			RDD::TextureSubresource subres;
			subres.aspect = RDD::TEXTURE_ASPECT_COLOR;
			subres.layer = p_layer;
			subres.mipmap = i;
			driver->texture_get_copyable_layout(tex->driver_id, subres, &mip_layouts[i]);

			// Assuming layers are tightly packed. If this is not true on some driver, we must modify the copy algorithm.
			DEV_ASSERT(mip_layouts[i].layer_pitch == mip_layouts[i].size / tex->layers);

			work_buffer_size = STEPIFY(work_buffer_size, work_mip_alignment) + mip_layouts[i].size;
		}

		RDD::BufferID tmp_buffer = driver->buffer_create(work_buffer_size, RDD::BUFFER_USAGE_TRANSFER_TO_BIT, RDD::MEMORY_ALLOCATION_TYPE_CPU);
		ERR_FAIL_COND_V(!tmp_buffer, Vector<uint8_t>());

		thread_local LocalVector<RDD::BufferTextureCopyRegion> command_buffer_texture_copy_regions_vector;
		command_buffer_texture_copy_regions_vector.clear();

		uint32_t w = tex->width;
		uint32_t h = tex->height;
		uint32_t d = tex->depth;
		for (uint32_t i = 0; i < tex->mipmaps; i++) {
			RDD::BufferTextureCopyRegion copy_region;
			copy_region.buffer_offset = mip_layouts[i].offset;
			copy_region.texture_subresources.aspect = tex->read_aspect_flags;
			copy_region.texture_subresources.mipmap = i;
			copy_region.texture_subresources.base_layer = p_layer;
			copy_region.texture_subresources.layer_count = 1;
			copy_region.texture_region_size.x = w;
			copy_region.texture_region_size.y = h;
			copy_region.texture_region_size.z = d;