rtx: add r_lightmap cvar, fix #75

ref_vk/shaders/ray.rchit

@@ -87,7 +87,7 @@ void main() {
     const vec4 uv_lods = UVDerivsFromRayCone(gl_WorldRayDirectionEXT, normal, ray_cone_width, uvs, pos, matWorldRotation);
     const vec4 tex_color = textureGrad(textures[nonuniformEXT(tex_index)], texture_uv, uv_lods.xy, uv_lods.zw);
     //const vec3 base_color = pow(tex_color.rgb, vec3(2.));
-    const vec3 base_color = tex_color.rgb;// pow(tex_color.rgb, vec3(2.));
+    const vec3 base_color = ((push_constants.flags & PUSH_FLAG_LIGHTMAP_ONLY) != 0) ? vec3(1.) : tex_color.rgb;// pow(tex_color.rgb, vec3(2.));
     /* tex_color = pow(tex_color, vec4(2.)); */
     /* const vec3 base_color = tex_color.rgb; */
 

ref_vk/shaders/ray_interop.h

@@ -84,6 +84,8 @@ struct LightCluster {
 	uint8_t emissive_surfaces[MAX_VISIBLE_SURFACE_LIGHTS];
 };
 
+#define PUSH_FLAG_LIGHTMAP_ONLY	0x01
+
 struct PushConstants {
 	float time;
 	uint random_seed;
@@ -91,6 +93,7 @@ struct PushConstants {
 	float prev_frame_blend_factor;
 	float pixel_cone_spread_angle;
 	uint debug_light_index_begin, debug_light_index_end;
+	uint flags;
 };
 
 #undef PAD

ref_vk/vk_cvar.c

@@ -17,4 +17,5 @@ void VK_LoadCvars( void )
 
 	vk_rtx_light_begin = gEngine.Cvar_Get( "vk_rtx_light_begin", "0", 0, "DEBUG: disable lights with index lower than this");
 	vk_rtx_light_end = gEngine.Cvar_Get( "vk_rtx_light_end", "0", 0, "DEBUG: disable lights with index higher than this ");
+	r_lightmap = gEngine.Cvar_Get( "r_lightmap", "0", FCVAR_CHEAT, "lightmap debugging tool" );
 }

ref_vk/vk_cvar.h

@@ -13,6 +13,7 @@ void VK_LoadCvars( void );
 	X(vk_rtx_prev_frame_blend_factor) \
 	X(vk_rtx_light_begin) \
 	X(vk_rtx_light_end) \
+	X(r_lightmap) \
 
 #define EXTERN_CVAR(cvar) extern cvar_t *cvar;
 DECLARE_CVAR(EXTERN_CVAR)

ref_vk/vk_rtx.c

@@ -672,6 +672,7 @@ static qboolean rayTrace( VkCommandBuffer cmdbuf, VkImage frame_dst, float fov_a
 			.pixel_cone_spread_angle = atanf((2.0f*tanf(fov_angle_y * 0.5f)) / (float)FRAME_HEIGHT),
 			.debug_light_index_begin = (uint32_t)(vk_rtx_light_begin->value),
 			.debug_light_index_end = (uint32_t)(vk_rtx_light_end->value),
+			.flags = r_lightmap->value ? PUSH_FLAG_LIGHTMAP_ONLY : 0,
 		};
 		vkCmdPushConstants(cmdbuf, g_rtx.descriptors.pipeline_layout, VK_SHADER_STAGE_RAYGEN_BIT_KHR | VK_SHADER_STAGE_CLOSEST_HIT_BIT_KHR | VK_SHADER_STAGE_ANY_HIT_BIT_KHR, 0, sizeof(push_constants), &push_constants);
 	}