From 852c395fb770e10b8787fa9a76ff4957b090ad6b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Henrik=20Rydg=C3=A5rd?= <hrydgard@gmail.com>
Date: Tue, 9 Aug 2022 16:00:41 +0200
Subject: [PATCH] Texcoord attrs must be called a_texcoord0, this should be
 fixed. Oh well.

Also small fix for depth in float-depal.
---
 Common/GPU/ShaderWriter.cpp            |  2 ++
 GPU/Common/DepalettizeShaderCommon.cpp | 22 ++++++++++++++++------
 GPU/Common/TextureCacheCommon.cpp      |  3 +--
 3 files changed, 19 insertions(+), 8 deletions(-)

diff --git a/Common/GPU/ShaderWriter.cpp b/Common/GPU/ShaderWriter.cpp
index da3a48e5c3..1671d5d6a5 100644
--- a/Common/GPU/ShaderWriter.cpp
+++ b/Common/GPU/ShaderWriter.cpp
@@ -14,6 +14,7 @@ const char * const vulkan_glsl_preamble_fs =
 "#extension GL_ARB_shader_image_load_store : enable\n"
 "#define splat3(x) vec3(x)\n"
 "#define DISCARD discard\n"
+"precision lowp float;\n"
 "precision highp int;\n"
 "\n";
 
@@ -131,6 +132,7 @@ void ShaderWriter::Preamble(const char **gl_extensions, size_t num_gl_extensions
 		case ShaderStage::Fragment:
 			C("#define DISCARD discard\n");
 			if (lang_.gles) {
+				C("precision lowp float;\n");
 				if (lang_.glslES30) {
 					C("precision highp int;\n");
 				}
diff --git a/GPU/Common/DepalettizeShaderCommon.cpp b/GPU/Common/DepalettizeShaderCommon.cpp
index ad53268760..45e6dba76e 100644
--- a/GPU/Common/DepalettizeShaderCommon.cpp
+++ b/GPU/Common/DepalettizeShaderCommon.cpp
@@ -31,7 +31,7 @@
 
 static const InputDef vsInputs[2] = {
 	{ "vec2", "a_position", Draw::SEM_POSITION, },
-	{ "vec2", "a_texcoord", Draw::SEM_TEXCOORD0, },
+	{ "vec2", "a_texcoord0", Draw::SEM_TEXCOORD0, },
 };
 
 // TODO: Deduplicate with DepalettizeCommon.cpp
@@ -135,6 +135,12 @@ void GenerateDepalShaderFloat(ShaderWriter &writer, const DepalConfig &config, c
 	const int shift = config.shift;
 	const int mask = config.mask;
 
+	if (config.pixelFormat == GE_FORMAT_DEPTH16) {
+		DepthScaleFactors factors = GetDepthScaleFactors();
+		writer.ConstFloat("z_scale", factors.scale);
+		writer.ConstFloat("z_offset", factors.offset);
+	}
+
 	float index_multiplier = 1.0f;
 	// pixelformat is the format of the texture we are sampling.
 	bool formatOK = true;
@@ -216,9 +222,14 @@ void GenerateDepalShaderFloat(ShaderWriter &writer, const DepalConfig &config, c
 	case GE_FORMAT_DEPTH16:
 	{
 		// TODO: I think we can handle most scenarios here, but texturing from depth buffers requires an extension on ES 2.0 anyway.
-		if ((mask & (mask + 1)) == 0 && shift < 16) {
+		if (shift < 16) {
 			index_multiplier = 1.0f / (float)(1 << shift);
-			truncate_cpy(lookupMethod, "index.r");
+			truncate_cpy(lookupMethod, "((index.x - z_offset) * z_scale)");
+
+			if ((mask & (mask + 1)) != 0) {
+				// But we'll try with the above anyway.
+				formatOK = false;
+			}
 		} else {
 			formatOK = false;
 		}
@@ -262,12 +273,11 @@ void GenerateDepalFs(char *buffer, const DepalConfig &config, const ShaderLangua
 	case GLSL_1xx:
 		GenerateDepalShaderFloat(writer, config, lang);
 		break;
-	case GLSL_3xx:
 	case GLSL_VULKAN:
+	case GLSL_3xx:
 	case HLSL_D3D11:
 		GenerateDepalShader300(writer, config, lang);
 		break;
-		break;
 	default:
 		_assert_msg_(false, "Depal shader language not supported: %d", (int)lang.shaderLanguage);
 	}
@@ -277,7 +287,7 @@ void GenerateDepalFs(char *buffer, const DepalConfig &config, const ShaderLangua
 void GenerateDepalVs(char *buffer, const ShaderLanguageDesc &lang) {
 	ShaderWriter writer(buffer, lang, ShaderStage::Vertex, nullptr, 0);
 	writer.BeginVSMain(vsInputs, Slice<UniformDef>::empty(), varyings);
-	writer.C("  v_texcoord = a_texcoord;\n");
+	writer.C("  v_texcoord = a_texcoord0;\n");
 	writer.C("  gl_Position = vec4(a_position, 0.0, 1.0);\n");
 	if (strlen(lang.viewportYSign)) {
 		writer.F("  gl_Position.y *= %s1.0;\n", lang.viewportYSign);
diff --git a/GPU/Common/TextureCacheCommon.cpp b/GPU/Common/TextureCacheCommon.cpp
index 979f4740fb..81741ed3f4 100644
--- a/GPU/Common/TextureCacheCommon.cpp
+++ b/GPU/Common/TextureCacheCommon.cpp
@@ -1897,7 +1897,6 @@ void TextureCacheCommon::ApplyTextureFramebuffer(VirtualFramebuffer *framebuffer
 
 			draw_->InvalidateCachedState();
 			InvalidateLastTexture();
-
 			return;
 		}
 
@@ -1922,10 +1921,10 @@ void TextureCacheCommon::ApplyTextureFramebuffer(VirtualFramebuffer *framebuffer
 		shaderApply.Use();
 
 		draw_->BindFramebufferAsTexture(framebuffer->fbo, 0, depth ? Draw::FB_DEPTH_BIT : Draw::FB_COLOR_BIT, 0);
+		draw_->BindTexture(1, clutTexture);
 		Draw::SamplerState *nearest = depalShaderCache_->GetSampler();
 		draw_->BindSamplerStates(0, 1, &nearest);
 		draw_->BindSamplerStates(1, 1, &nearest);
-		draw_->BindTexture(1, clutTexture);
 
 		shaderApply.Shade();
 		draw_->BindTexture(0, nullptr);