Get desktop GL conformance tests to build

The target for these tests is angle_deqp_gl_tests.

Bug: angleproject:7533
Change-Id: I290822671d99da020f9a6a1f02bee43987644bf9
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3766435
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Eddie Hatfield <eddiehatfield@google.com>
Reviewed-by: Geoff Lang <geofflang@chromium.org>

samples/BUILD.gn

@@ -31,6 +31,7 @@ angle_source_set("sample_util") {
     "../:libGLESv1_CM",
     "../:libGLESv2",
   ]
+
   public_deps = [
     "../:angle_common",
     "../util:angle_test_utils",
@@ -42,6 +43,10 @@ angle_source_set("sample_util") {
     ":sample_util_config",
     "../:no_gl_prototypes",
   ]
+
+  if (angle_expose_wgl_entry_points) {
+    defines = [ "ANGLE_EXPOSE_WGL_ENTRY_POINTS" ]
+  }
 }
 
 template("angle_sample") {
@@ -90,6 +95,10 @@ angle_sample("hello_triangle") {
   sources = [ "hello_triangle/HelloTriangle.cpp" ]
 }
 
+angle_sample("hello_triangle_gl") {
+  sources = [ "hello_triangle_gl/HelloTriangleGL.cpp" ]
+}
+
 angle_sample("mip_map_2d") {
   sources = [ "mip_map_2d/MipMap2D.cpp" ]
 }

samples/hello_triangle_gl/HelloTriangleGL.cpp

@@ -0,0 +1,85 @@
+//
+// Copyright 2022 The ANGLE Project Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+
+//            Based on Hello_Triangle.c from
+// Book:      OpenGL(R) ES 2.0 Programming Guide
+// Authors:   Aaftab Munshi, Dan Ginsburg, Dave Shreiner
+// ISBN-10:   0321502795
+// ISBN-13:   9780321502797
+// Publisher: Addison-Wesley Professional
+// URLs:      http://safari.informit.com/9780321563835
+//            http://www.opengles-book.com
+
+#include "SampleApplication.h"
+
+#include "util/shader_utils.h"
+
+// Practically identical to the normal HelloTrianglesSample, but uses desktop GL instead.
+class HelloTriangleGLSample : public SampleApplication
+{
+  public:
+    HelloTriangleGLSample(int argc, char **argv)
+        : SampleApplication("HelloTriangle", argc, argv, ClientType::GL3_3_CORE)
+    {}
+
+    bool initialize() override
+    {
+        constexpr char kVS[] = R"(attribute vec4 vPosition;
+void main()
+{
+    gl_Position = vPosition;
+})";
+
+        constexpr char kFS[] = R"(precision mediump float;
+void main()
+{
+    gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
+})";
+
+        mProgram = CompileProgram(kVS, kFS);
+        if (!mProgram)
+        {
+            return false;
+        }
+
+        glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
+
+        return true;
+    }
+
+    void destroy() override { glDeleteProgram(mProgram); }
+
+    void draw() override
+    {
+        GLfloat vertices[] = {
+            0.0f, 0.5f, 0.0f, -0.5f, -0.5f, 0.0f, 0.5f, -0.5f, 0.0f,
+        };
+
+        // Set the viewport
+        glViewport(0, 0, getWindow()->getWidth(), getWindow()->getHeight());
+
+        // Clear the color buffer
+        glClear(GL_COLOR_BUFFER_BIT);
+
+        // Use the program object
+        glUseProgram(mProgram);
+
+        // Load the vertex data
+        glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, vertices);
+        glEnableVertexAttribArray(0);
+
+        glDrawArrays(GL_TRIANGLES, 0, 3);
+    }
+
+  private:
+    GLuint mProgram;
+};
+
+int main(int argc, char **argv)
+{
+    HelloTriangleGLSample app(argc, argv);
+    return app.run();
+}

samples/sample_util/SampleApplication.cpp

@@ -139,6 +139,18 @@ SampleApplication::SampleApplication(std::string name,
             glMinorVersion = 3;
             profileMask    = EGL_CONTEXT_OPENGL_COMPATIBILITY_PROFILE_BIT;
             break;
+        case ClientType::GL4_6_CORE:
+            eglClientType  = EGL_OPENGL_API;
+            glMajorVersion = 4;
+            glMinorVersion = 6;
+            profileMask    = EGL_CONTEXT_OPENGL_CORE_PROFILE_BIT;
+            break;
+        case ClientType::GL4_6_COMPATIBILITY:
+            eglClientType  = EGL_OPENGL_API;
+            glMajorVersion = 4;
+            glMinorVersion = 6;
+            profileMask    = EGL_CONTEXT_OPENGL_COMPATIBILITY_PROFILE_BIT;
+            break;
         default:
             UNREACHABLE();
     }
@@ -161,10 +173,16 @@ SampleApplication::SampleApplication(std::string name,
     }
     else
     {
-        mGLWindow = mEGLWindow =
+#if defined(ANGLE_EXPOSE_WGL_ENTRY_POINTS)
+        mGLWindow = WGLWindow::New(eglClientType, glMajorVersion, glMinorVersion, profileMask);
+        mEntryPointsLib.reset(angle::OpenSharedLibrary("opengl32", angle::SearchType::ModuleDir));
+        mDriverType = angle::GLESDriverType::SystemWGL;
+#else
+        mGLWindow   = mEGLWindow =
             EGLWindow::New(eglClientType, glMajorVersion, glMinorVersion, profileMask);
         mEntryPointsLib.reset(
             angle::OpenSharedLibrary(ANGLE_EGL_LIBRARY_NAME, angle::SearchType::ModuleDir));
+#endif  // defined(ANGLE_EXPOSE_WGL_ENTRY_POINTS)
     }
 }
 

samples/sample_util/SampleApplication.h

@@ -37,6 +37,8 @@ enum class ClientType
     ES3_1,
     GL3_3_CORE,
     GL3_3_COMPATIBILITY,
+    GL4_6_CORE,
+    GL4_6_COMPATIBILITY,
 };
 
 class SampleApplication