Shader breaks when activating Normal or Specular Mapping on Iris 1.7.0 and DH 2.0

[pnk2u]

What happened?

Activating Normal or Specular Mapping breaks the shader (Minecraft falls back to Vanilla shaders).
Given the error code and through trial and error, one solution I found was to change these lines in the deferred3.glsl file:

#ifdef DISTANT_HORIZONS
		if (!is_dh_terrain) {
#endif

	#ifdef NORMAL_MAPPING
		normal = decode_unit_vector(gbuffer_data_1.xy);
	#endif

	#ifdef SPECULAR_MAPPING
		bool parallax_shadow;
		vec4 specular_map = vec4(unpack_unorm_2x8(gbuffer_data_1.z), unpack_unorm_2x8(gbuffer_data_1.w));
		decode_specular_map(specular_map, material, parallax_shadow);
	#elif defined NORMAL_MAPPING
		bool parallax_shadow = gbuffer_data_1.z >= 0.5;
	#endif
#ifdef DISTANT_HORIZONS
		}
#endif

to

//  #ifdef DISTANT_HORIZONS
			

	#ifdef NORMAL_MAPPING
		 if (!is_dh_terrain) {
		normal = decode_unit_vector(gbuffer_data_1.xy);
		 }
	#endif

	#ifdef SPECULAR_MAPPING
		bool parallax_shadow;
		if (!is_dh_terrain) {
		vec4 specular_map = vec4(unpack_unorm_2x8(gbuffer_data_1.z), unpack_unorm_2x8(gbuffer_data_1.w));
		decode_specular_map(specular_map, material, parallax_shadow);
		}
		
	#elif defined NORMAL_MAPPING
		if (!is_dh_terrain) {
		bool parallax_shadow = gbuffer_data_1.z >= 0.5;
		}
	#endif
	
//  #endif

which leads to the both Normal and Specular Maps and seperately the DH chunks to render as expected and the shader to not break, effectively fixing the issue.

Minecraft Version

Other

Which shader mod are you using?

Iris

Shader mod version

1.7.0

Shader settings

shadowDistance=128.0
COLORED_LIGHTS=true
BLOCKLIGHT_G=0.69
PIXELATED_SHADOWS=true
SNELLS_WINDOW=true
POM_DEPTH=0.15
WATER_WAVE_ITERATIONS=7
WATER_WAVE_LACUNARITY=1.23
DIRECTIONAL_LIGHTMAPS_INTENSITY=0.45
WATER_CAUSTICS=true
WATER_WAVE_FREQUENCY=0.78
WATER_REFRACTION_INTENSITY=1.01
BOX_MODE=BOX_MODE_COLOR
SPECULAR_MAPPING=true
WATER_ABSORPTION_B_UNDERWATER=0.01
WATER_WAVE_PERSISTENCE=0.71
WATER_ABSORPTION_G_UNDERWATER=0.04
WATER_WAVE_STRENGTH=0.63
WATER_ABSORPTION_R=0.26
WATER_SCATTERING_UNDERWATER=0.02
BLOCKLIGHT_B=0.81
WATER_ABSORPTION_R_UNDERWATER=0.14
BOX_LINE_WIDTH=3.0
WATER_WAVE_SPEED_STILL=0.77
POM_SAMPLES=70
POM_SHADOW=true
POM_SHADOW_SAMPLES=60
BOX_EMISSION=0.36
HANDHELD_LIGHTING=true
SH_SKYLIGHT=true
NORMAL_MAPPING=true
BLOCK_ENTITY_SHADOWS=true
MOON_B=0.95
BOX_COLOR_B=0.42
WATER_ABSORPTION_B=0.19
MOON_G=0.91
BOX_COLOR_G=0.01
WATER_ABSORPTION_G=0.22
POM=true
WATER_SCATTERING=0.05
SHADING_STRENGTH=2.00
shadowMapResolution=1024
PIXELATED_SHADOWS_RESOLUTION=128
DIRECTIONAL_LIGHTMAPS=true
MOON_R=0.68
CLOUD_SHADOWS=true
WATER_WAVE_SPEED_FLOWING=0.90

Relevant log output

deferred3.fsh: deferred3.fsh: 0(1685) : error C1503: undefined variable "parallax_shadow"

[sixthsurge]

fixed in dev branch