[vulkan] Add a level of indirection to shadow matrices

Batching shadow map rendering needs be able to reference matrices for
multiple lights in a single batch, but the only input is the view index,
so use that to look up the matrix index rather than using it to index
the matrices directly (modulo the base index that's still there).

include/QF/Vulkan/qf_lighting.h

@@ -85,6 +85,7 @@ typedef struct lightingframe_s {
 	VkDescriptorSet attach_set;
 
 	VkBuffer    shadowmat_buffer;
+	VkBuffer    shadowmat_id_buffer;
 	VkBuffer    light_buffer;
 	VkBuffer    render_buffer;
 	VkBuffer    style_buffer;

libs/video/renderer/vulkan/shader/alias_shadow.vert

@@ -6,6 +6,10 @@ layout (set = 0, binding = 0) buffer ShadowView {
 	mat4x4      shadowView[];
 };
 
+layout (set = 0, binding = 1) buffer ShadowId {
+	uint        shadowId[];
+};
+
 layout (push_constant) uniform PushConstants {
 	mat4 Model;
 	float blend;
@@ -21,5 +25,6 @@ void
 main (void)
 {
 	vec4 pos = mix (vertexa, vertexb, blend);
-	gl_Position = shadowView[MatrixBase + gl_ViewIndex] * (Model * pos);
+	uint matid = shadowId[MatrixBase + gl_ViewIndex];
+	gl_Position = shadowView[matid] * (Model * pos);
 }

libs/video/renderer/vulkan/shader/bsp_shadow.vert

@@ -6,6 +6,10 @@ layout (set = 0, binding = 0) buffer ShadowView {
 	mat4x4      shadowView[];
 };
 
+layout (set = 0, binding = 1) buffer ShadowId {
+	uint        shadowId[];
+};
+
 layout (push_constant) uniform PushConstants {
 	uint MatrixBase;
 };
@@ -25,5 +29,6 @@ void
 main (void)
 {
 	vec4        pos = vec4 (vertex * entities[entid].transform, 1);
-	gl_Position = shadowView[MatrixBase + gl_ViewIndex] * pos;
+	uint matid = shadowId[MatrixBase + gl_ViewIndex];
+	gl_Position = shadowView[matid] * pos;
 }

libs/video/renderer/vulkan/shader/iqm.vert

@@ -13,6 +13,10 @@ layout (set = 1, binding = 0) buffer ShadowView {
 	mat4x4      shadowView[];
 };
 
+layout (set = 1, binding = 1) buffer ShadowId {
+	uint        shadowId[];
+};
+
 layout (set = 3, binding = 0) buffer Bones {
 	// NOTE these are transposed, so v * m
 	mat3x4      bones[];
@@ -49,7 +53,8 @@ main (void)
 	m += mat3x4(1,0,0,0,0,1,0,0,0,0,1,0) * (1 - dot(vweights, vec4(1,1,1,1)));
 	vec4        pos = Model * vec4 (vec4(vposition, 1) * m, 1);
 	if (IQMShadow) {
-		gl_Position = shadowView[MatrixBase + gl_ViewIndex] * pos;
+		uint matid = shadowId[MatrixBase + gl_ViewIndex];
+		gl_Position = shadowView[matid] * pos;
 	} else {
 		gl_Position = Projection3d * (View[gl_ViewIndex] * pos);
 	}

libs/video/renderer/vulkan/vulkan_lighting.c

@@ -1090,6 +1090,8 @@ Vulkan_Lighting_Setup (vulkan_ctx_t *ctx)
 									+ 3 * sizeof (qfv_resobj_t)
 									// light matrices
 									+ sizeof (qfv_resobj_t[frames])
+									// light matrix ids
+									+ sizeof (qfv_resobj_t[frames])
 									// light ids
 									+ sizeof (qfv_resobj_t[frames])
 									// light data
@@ -1104,7 +1106,7 @@ Vulkan_Lighting_Setup (vulkan_ctx_t *ctx)
 		.name = "lights",
 		.va_ctx = ctx->va_ctx,
 		.memory_properties = VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT,
-		.num_objects = 2 + 3 + 6 * frames,
+		.num_objects = 2 + 3 + 7 * frames,
 		.objects = (qfv_resobj_t *) &lctx->light_resources[1],
 	};
 	auto splat_verts = lctx->light_resources->objects;
@@ -1113,7 +1115,8 @@ Vulkan_Lighting_Setup (vulkan_ctx_t *ctx)
 	auto default_view_cube = &default_map[1];
 	auto default_view_2d = &default_view_cube[1];
 	auto light_mats = &default_view_2d[1];
-	auto light_ids = &light_mats[frames];
+	auto light_mat_ids = &light_mats[frames];
+	auto light_ids = &light_mat_ids[frames];
 	auto light_data = &light_ids[frames];
 	auto light_render = &light_data[frames];
 	auto light_styles = &light_render[frames];
@@ -1237,6 +1240,16 @@ Vulkan_Lighting_Setup (vulkan_ctx_t *ctx)
 						| VK_BUFFER_USAGE_TRANSFER_DST_BIT,
 			},
 		};
+		light_mat_ids[i] = (qfv_resobj_t) {
+			.name = va (ctx->va_ctx, "matrix ids:%zd", i),
+			.type = qfv_res_buffer,
+			.buffer = {
+				// never need more than 6 matrices per light
+				.size = sizeof (uint32_t[MaxLights * 6]),
+				.usage = VK_BUFFER_USAGE_STORAGE_BUFFER_BIT
+						| VK_BUFFER_USAGE_TRANSFER_DST_BIT,
+			},
+		};
 	}
 
 	QFV_CreateResource (device, lctx->light_resources);
@@ -1266,6 +1279,7 @@ Vulkan_Lighting_Setup (vulkan_ctx_t *ctx)
 			.lights_set = QFV_DSManager_AllocSet (lights_mgr),
 			.attach_set = QFV_DSManager_AllocSet (attach_mgr),
 			.shadowmat_buffer = light_mats[i].buffer.buffer,
+			.shadowmat_id_buffer = light_mat_ids[i].buffer.buffer,
 			.light_buffer = light_data[i].buffer.buffer,
 			.render_buffer = light_render[i].buffer.buffer,
 			.style_buffer = light_styles[i].buffer.buffer,
@@ -1289,6 +1303,8 @@ Vulkan_Lighting_Setup (vulkan_ctx_t *ctx)
 		VkDescriptorBufferInfo bufferInfo[] = {
 			{	.buffer = lframe->shadowmat_buffer,
 				.offset = 0, .range = VK_WHOLE_SIZE, },
+			{	.buffer = lframe->shadowmat_id_buffer,
+				.offset = 0, .range = VK_WHOLE_SIZE, },
 			{	.buffer = lframe->id_buffer,
 				.offset = 0, .range = VK_WHOLE_SIZE, },
 			{	.buffer = lframe->light_buffer,
@@ -1307,39 +1323,45 @@ Vulkan_Lighting_Setup (vulkan_ctx_t *ctx)
 				.descriptorCount = 1,
 				.descriptorType = VK_DESCRIPTOR_TYPE_STORAGE_BUFFER,
 				.pBufferInfo = &bufferInfo[0], },
+			{	.sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET,
+				.dstSet = lframe->shadowmat_set,
+				.dstBinding = 1,
+				.descriptorCount = 1,
+				.descriptorType = VK_DESCRIPTOR_TYPE_STORAGE_BUFFER,
+				.pBufferInfo = &bufferInfo[1], },
 
 			{	.sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET,
 				.dstSet = lframe->lights_set,
 				.dstBinding = 0,
 				.descriptorCount = 1,
 				.descriptorType = VK_DESCRIPTOR_TYPE_STORAGE_BUFFER,
-				.pBufferInfo = &bufferInfo[1], },
+				.pBufferInfo = &bufferInfo[2], },
 			{	.sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET,
 				.dstSet = lframe->lights_set,
 				.dstBinding = 1,
 				.descriptorCount = 1,
 				.descriptorType = VK_DESCRIPTOR_TYPE_STORAGE_BUFFER,
-				.pBufferInfo = &bufferInfo[2], },
+				.pBufferInfo = &bufferInfo[3], },
 			{	.sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET,
 				.dstSet = lframe->lights_set,
 				.dstBinding = 2,
 				.descriptorCount = 1,
 				.descriptorType = VK_DESCRIPTOR_TYPE_STORAGE_BUFFER,
-				.pBufferInfo = &bufferInfo[3], },
+				.pBufferInfo = &bufferInfo[4], },
 			{	.sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET,
 				.dstSet = lframe->lights_set,
 				.dstBinding = 3,
 				.descriptorCount = 1,
 				.descriptorType = VK_DESCRIPTOR_TYPE_STORAGE_BUFFER,
-				.pBufferInfo = &bufferInfo[4], },
+				.pBufferInfo = &bufferInfo[5], },
 			{	.sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET,
 				.dstSet = lframe->lights_set,
 				.dstBinding = 4,
 				.descriptorCount = 1,
 				.descriptorType = VK_DESCRIPTOR_TYPE_STORAGE_BUFFER,
-				.pBufferInfo = &bufferInfo[5], },
+				.pBufferInfo = &bufferInfo[6], },
 		};
-		dfunc->vkUpdateDescriptorSets (device->dev, 6, bufferWrite, 0, 0);
+		dfunc->vkUpdateDescriptorSets (device->dev, 7, bufferWrite, 0, 0);
 	}
 
 	make_default_map (64, lctx->default_map, ctx);
@@ -1501,6 +1523,19 @@ upload_light_matrices (lightingctx_t *lctx, vulkan_ctx_t *ctx)
 		QFV_PacketCopyBuffer (packet, lframe->shadowmat_buffer, 0, bb);
 	}
 	QFV_PacketSubmit (packet);
+
+	// FIXME temporary until batched shadow rendering is implemented
+	packet = QFV_PacketAcquire (ctx->staging);
+	size_t id_size = sizeof (uint32_t[MaxLights * 6]);
+	uint32_t *id_data = QFV_PacketExtend (packet, id_size);
+	for (int i = 0; i < MaxLights * 6; i++) {
+		id_data[i] = i;
+	}
+	for (size_t i = 0; i < lctx->frames.size; i++) {
+		auto lframe = &lctx->frames.a[i];
+		QFV_PacketCopyBuffer (packet, lframe->shadowmat_id_buffer, 0, bb);
+	}
+	QFV_PacketSubmit (packet);
 }
 
 static void
@@ -1839,10 +1874,10 @@ build_shadow_maps (lightingctx_t *lctx, vulkan_ctx_t *ctx)
 
 		switch (lr->numLayers) {
 			case 6:
-				lr->renderpass_index = 2;
+				lr->renderpass_index = 6 - 1;
 				break;
 			case num_cascade:
-				lr->renderpass_index = 1;
+				lr->renderpass_index = num_cascade - 1;
 				break;
 			case 1:
 				lr->renderpass_index = 0;