Adjust GL SPIR-V shader test demo to do opengl-unique things

* E.g. not specify a binding and let that be done at runtime, or global
  variables not in constant buffers.

util/test/demos/gl/gl_spirv_shader.cpp

@@ -29,7 +29,7 @@ struct SPIRV_Shader : OpenGLGraphicsTest
   static constexpr const char *Description = "Draws using a SPIR-V shader pipeline.";
 
   std::string vertex = R"EOSHADER(
-#version 420 core
+#version 430 core
 
 layout(location = 0) in vec3 Position;
 layout(location = 1) in vec4 Color;
@@ -39,25 +39,21 @@ layout(location = 0) out vec4 oPos;
 layout(location = 1) out vec4 oCol;
 layout(location = 2) out vec2 oUV;
 
-layout(binding = 0, std140) uniform vsconstsbuf
-{
-  vec4 offset;
-  vec4 scale;
-
-  vec2 UVscroll;
-} vsconsts;
+layout(location = 2) uniform vec4 offset;
+layout(location = 8) uniform vec4 scale;
+layout(location = 13) uniform vec4 UVscroll;
 
 void main()
 {
-	gl_Position = oPos = vec4(Position.xyz * vsconsts.scale.xyz + vsconsts.offset.xyz, 1);
+	gl_Position = oPos = vec4(Position.xyz * scale.xyz + offset.xyz, 1);
 	oCol = Color;
-	oUV = UV + vsconsts.UVscroll.xy;
+	oUV = UV + UVscroll.xy;
 }
 
 )EOSHADER";
 
   std::string pixel = R"EOSHADER(
-#version 420 core
+#version 430 core
 
 layout(location = 0) in vec4 iPos;
 layout(location = 1) in vec4 iCol;
@@ -65,16 +61,13 @@ layout(location = 2) in vec2 iUV;
 
 layout(location = 0) out vec4 Color;
 
-layout(binding = 0) uniform sampler2D tex2D;
+layout(location = 5) uniform sampler2D tex2D;
 
-layout(binding = 1, std140) uniform fsconstsbuf
-{
-  vec4 tint;
-} fsconsts;
+layout(location = 7) uniform vec4 tint;
 
 void main()
 {
-	Color = (iCol + fsconsts.tint) * textureLod(tex2D, iUV, 0.0f);
+	Color = (iCol + tint) * textureLod(tex2D, iUV, 0.0f);
 }
 
 )EOSHADER";
@@ -127,6 +120,8 @@ void main()
 
     glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, 4, 4, GL_RGBA, GL_UNSIGNED_BYTE, pixels);
 
+    glBindTexture(GL_TEXTURE_2D, 0);
+
     GLuint vsbuf = MakeBuffer();
     glBindBuffer(GL_UNIFORM_BUFFER, vsbuf);
     glBufferStorage(GL_UNIFORM_BUFFER, sizeof(Vec4f) * 3, 0, GL_DYNAMIC_STORAGE_BIT);
@@ -147,10 +142,10 @@ void main()
       GLuint vs = glCreateShader(GL_VERTEX_SHADER);
       GLuint fs = glCreateShader(GL_FRAGMENT_SHADER);
 
-      std::vector<uint32_t> vsSPIRV =
-          CompileShaderToSpv(vertex, ShaderLang::glsl, ShaderStage::vert, "main");
-      std::vector<uint32_t> fsSPIRV =
-          CompileShaderToSpv(pixel, ShaderLang::glsl, ShaderStage::frag, "main");
+      std::vector<uint32_t> vsSPIRV = CompileShaderToSpv(
+          vertex, SPIRVTarget::opengl, ShaderLang::glsl, ShaderStage::vert, "main");
+      std::vector<uint32_t> fsSPIRV = CompileShaderToSpv(
+          pixel, SPIRVTarget::opengl, ShaderLang::glsl, ShaderStage::frag, "main");
 
       glShaderBinary(1, &vs, GL_SHADER_BINARY_FORMAT_SPIR_V, vsSPIRV.data(),
                      (GLsizei)vsSPIRV.size() * 4);
@@ -219,6 +214,9 @@ void main()
 
     fsdata = Vec4f(0.1f, 0.2f, 0.3f, 1.0f);
 
+    glActiveTexture(GL_TEXTURE9);
+    glBindTexture(GL_TEXTURE_2D, tex);
+
     while(Running())
     {
       float col[] = {0.4f, 0.5f, 0.6f, 1.0f};
@@ -227,13 +225,27 @@ void main()
       vsdata.UVscroll.x += 0.01f;
       vsdata.UVscroll.y += 0.02f;
 
+      for(GLuint prog : {glslprogram, spirvprogram})
+      {
+        glUseProgram(prog);
+        // tex2D location 5
+        glUniform1i(5, 9);
+
+        // offset location 2
+        // scale location 8
+        // UVscroll location 13
+        glUniform4fv(2, 1, &vsdata.offset.x);
+        glUniform4fv(8, 1, &vsdata.scale.x);
+        glUniform4fv(13, 1, &vsdata.UVscroll.x);
+
+        // tint location 7
+        glUniform4fv(7, 1, &fsdata.x);
+      }
+
       glBindVertexArray(vao);
 
       glViewport(0, 0, GLsizei(screenWidth) >> 1, GLsizei(screenHeight));
 
-      glNamedBufferSubData(vsbuf, 0, sizeof(vsdata), &vsdata);
-      glNamedBufferSubData(fsbuf, 0, sizeof(fsdata), &fsdata);
-
       glUseProgram(glslprogram);
       glDrawArrays(GL_TRIANGLES, 0, 3);
 

util/test/demos/test_common.cpp

@@ -213,8 +213,8 @@ bool SpvCompilationSupported()
   return WEXITSTATUS(code) == 0;
 }
 
-std::vector<uint32_t> CompileShaderToSpv(const std::string &source_text, ShaderLang lang,
-                                         ShaderStage stage, const char *entry_point)
+std::vector<uint32_t> CompileShaderToSpv(const std::string &source_text, SPIRVTarget target,
+                                         ShaderLang lang, ShaderStage stage, const char *entry_point)
 {
   std::vector<uint32_t> ret;
 
@@ -243,6 +243,9 @@ std::vector<uint32_t> CompileShaderToSpv(const std::string &source_text, ShaderL
       case ShaderStage::comp: shader_kind = shaderc_compute_shader; break;
     }
 
+    if(target == SPIRVTarget::opengl)
+      shaderc_compile_options_set_target_env(opts, shaderc_target_env_opengl, 0);
+
     shaderc_compilation_result_t res = shaderc_compile_into_spv(
         shaderc, source_text.c_str(), source_text.size(), shader_kind, "inshader", entry_point, opts);
 

util/test/demos/test_common.h

@@ -41,6 +41,11 @@
 
 typedef uint8_t byte;
 
+enum class SPIRVTarget
+{
+  opengl,
+  vulkan
+};
 enum class ShaderLang
 {
   glsl,
@@ -57,8 +62,8 @@ enum class ShaderStage
 };
 
 bool SpvCompilationSupported();
-std::vector<uint32_t> CompileShaderToSpv(const std::string &source_text, ShaderLang lang,
-                                         ShaderStage stage, const char *entry_point);
+std::vector<uint32_t> CompileShaderToSpv(const std::string &source_text, SPIRVTarget target,
+                                         ShaderLang lang, ShaderStage stage, const char *entry_point);
 
 struct Vec2f
 {

util/test/demos/vk/vk_test.cpp

@@ -578,7 +578,8 @@ VkPipelineShaderStageCreateInfo VulkanGraphicsTest::CompileShaderModule(
 {
   VkShaderModule ret = VK_NULL_HANDLE;
 
-  std::vector<uint32_t> spirv = ::CompileShaderToSpv(source_text, lang, stage, entry_point);
+  std::vector<uint32_t> spirv =
+      ::CompileShaderToSpv(source_text, SPIRVTarget::vulkan, lang, stage, entry_point);
 
   if(spirv.empty())
     return {};