Combined array of images is starting to work ...

spirv_cross.cpp

@@ -3176,12 +3176,17 @@ bool Compiler::DummySamplerForCombinedImageHandler::handle(Op opcode, const uint
 		if (length < 3)
 			return false;
 
-		auto &type = compiler.get<SPIRType>(args[0]);
+		uint32_t result_type = args[0];
+		auto &type = compiler.get<SPIRType>(result_type);
 		bool separate_image =
 		    type.basetype == SPIRType::Image && type.image.sampled == 1 && type.image.dim != DimBuffer;
-		if (separate_image)
-			SPIRV_CROSS_THROW("Attempting to use arrays or structs of separate images. This is not possible to "
-			                  "statically remap to plain GLSL.");
+		if (!separate_image)
+			return true;
+
+		uint32_t id = args[1];
+		uint32_t ptr = args[2];
+		compiler.set<SPIRExpression>(id, "", result_type, true);
+		compiler.register_read(id, ptr, true);
 		break;
 	}
 
@@ -3233,16 +3238,26 @@ bool Compiler::CombinedImageSamplerHandler::handle(Op opcode, const uint32_t *ar
 		// but this seems ridiculously complicated for a problem which is easy to work around.
 		// Checking access chains like this assumes we don't have samplers or textures inside uniform structs, but this makes no sense.
 
-		auto &type = compiler.get<SPIRType>(args[0]);
+		uint32_t result_type = args[0];
+
+		auto &type = compiler.get<SPIRType>(result_type);
 		bool separate_image = type.basetype == SPIRType::Image && type.image.sampled == 1;
 		bool separate_sampler = type.basetype == SPIRType::Sampler;
-		if (separate_image)
-			SPIRV_CROSS_THROW("Attempting to use arrays or structs of separate images. This is not possible to "
-			                  "statically remap to plain GLSL.");
+		//if (separate_image)
+		//	SPIRV_CROSS_THROW("Attempting to use arrays or structs of separate images. This is not possible to "
+		//	                  "statically remap to plain GLSL.");
 		if (separate_sampler)
 			SPIRV_CROSS_THROW(
 			    "Attempting to use arrays or structs of separate samplers. This is not possible to statically "
 			    "remap to plain GLSL.");
+
+		if (separate_image)
+		{
+			uint32_t id = args[1];
+			uint32_t ptr = args[2];
+			compiler.set<SPIRExpression>(id, "", result_type, true);
+			compiler.register_read(id, ptr, true);
+		}
 		return true;
 	}
 
@@ -3325,6 +3340,7 @@ bool Compiler::CombinedImageSamplerHandler::handle(Op opcode, const uint32_t *ar
 			type = compiler.expression_type(args[2]);
 			type.self = sampled_type;
 			type.basetype = SPIRType::SampledImage;
+
 		}
 		else
 		{
@@ -3354,6 +3370,15 @@ bool Compiler::CombinedImageSamplerHandler::handle(Op opcode, const uint32_t *ar
 		if (old_flags.get(DecorationRelaxedPrecision))
 			new_flags.set(DecorationRelaxedPrecision);
 
+		// Propagate the array type for the original image as well.
+		auto *var = compiler.maybe_get_backing_variable(image_id);
+		if (var)
+		{
+			auto &parent_type = compiler.get<SPIRType>(var->basetype);
+			type.array = parent_type.array;
+			type.array_size_literal = parent_type.array_size_literal;
+		}
+
 		compiler.combined_image_samplers.push_back({ combined_id, image_id, sampler_id });
 	}
 

spirv_cross.hpp

@@ -384,6 +384,8 @@ public:
 	// so this can be added before compile() if desired.
 	//
 	// Combined image samplers originating from this set are always considered active variables.
+	// Arrays of separate samplers are not supported, but arrays of separate images are supported.
+	// Array of images + sampler -> Array of combined image samplers.
 	void build_combined_image_samplers();
 
 	// Gets a remapping for the combined image samplers.

spirv_glsl.cpp

@@ -3609,6 +3609,14 @@ void CompilerGLSL::emit_mix_op(uint32_t result_type, uint32_t id, uint32_t left,
 
 string CompilerGLSL::to_combined_image_sampler(uint32_t image_id, uint32_t samp_id)
 {
+	// Keep track of the array indices we have used to load the image.
+	// We'll need to use the same array index into the combined image sampler array.
+	auto image_expr = to_expression(image_id);
+	string array_expr;
+	auto array_index = image_expr.find_first_of('[');
+	if (array_index != string::npos)
+		array_expr = image_expr.substr(array_index, string::npos);
+
 	auto &args = current_function->arguments;
 
 	// For GLSL and ESSL targets, we must enumerate all possible combinations for sampler2D(texture2D, sampler) and redirect
@@ -3641,7 +3649,7 @@ string CompilerGLSL::to_combined_image_sampler(uint32_t image_id, uint32_t samp_
 		});
 
 		if (itr != end(combined))
-			return to_expression(itr->id);
+			return to_expression(itr->id) + array_expr;
 		else
 		{
 			SPIRV_CROSS_THROW(
@@ -3658,7 +3666,7 @@ string CompilerGLSL::to_combined_image_sampler(uint32_t image_id, uint32_t samp_
 		});
 
 		if (itr != end(combined_image_samplers))
-			return to_expression(itr->combined_id);
+			return to_expression(itr->combined_id) + array_expr;
 		else
 		{
 			SPIRV_CROSS_THROW("Cannot find mapping for combined sampler, was build_combined_image_samplers() used "