[Test] (Diligent, MG_Test): add scissor and blend state tests

- Verify scissor clipping leaves outside pixels untouched
- Verify alpha blend combines source/destination colors
- Update handoff to 10 passing Diligent tests

HANDOFF_DILIGENT.md

@@ -98,6 +98,11 @@ Working tree is clean.
   - `DrawsFromMobileGLState`
   - `DrawsTexturedFromMobileGLState`
   - `DrawsIndexedFromMobileGLState`
+  - `DrawsRealTexturedFromMobileGLState`
+  - `DrawsUniformFromMobileGLState`
+  - `DrawsToOffscreenFramebufferFromMobileGLState`
+  - `DrawsWithScissorFromMobileGLState`
+  - `DrawsWithBlendFromMobileGLState`
 
 ---
 
@@ -149,7 +154,7 @@ Verified locally on Turnip Adreno 750:
 - Local test result:
 
 ```
-[  PASSED  ] 8 tests
+[  PASSED  ] 10 tests
 ```
 
 ---
@@ -236,12 +241,12 @@ Notes:
    - [ ] `GetTexImage` / `CopyTexImage*` / indirect draws
 
 6. **Expand local test suite**
-   - Depth test visual test
+   - [x] Scissor test
-   - Stencil test
+   - [x] Blend test
-   - Blend test
+   - [x] Texture filtering / sampler state test
-   - Scissor test
+   - [x] framebuffer offscreen render-to-texture test
-   - Texture filtering / sampler state test
+   - [ ] Depth test visual test
-   - framebuffer offscreen render-to-texture test
+   - [ ] Stencil test
 
 ---
 

MobileGL/MG_Test/Backend/Diligent/SanityTest.cpp

@@ -495,3 +495,134 @@ void main() { Color = vec4(1.0, 0.0, 0.0, 1.0); }
     EXPECT_GT(corner[1], 200) << "corner should remain green after clear";
     EXPECT_LT(corner[0], 50) << "corner should not be red";
 }
+
+
+TEST(DiligentVulkanBackend, DrawsWithScissorFromMobileGLState) {
+    MobileGL::Initialize();
+
+    const char* vsSrc = R"(#version 330 core
+layout(location = 0) in vec2 Position;
+void main() { gl_Position = vec4(Position, 0.0, 1.0); }
+)";
+    const char* fsSrc = R"(#version 330 core
+out vec4 Color;
+void main() { Color = vec4(1.0, 0.0, 0.0, 1.0); }
+)";
+
+    const GLuint vs = CreateShader(GL_VERTEX_SHADER);
+    ShaderSource(vs, 1, &vsSrc, nullptr);
+    CompileShader(vs);
+    const GLuint fs = CreateShader(GL_FRAGMENT_SHADER);
+    ShaderSource(fs, 1, &fsSrc, nullptr);
+    CompileShader(fs);
+    const GLuint program = CreateProgram();
+    AttachShader(program, vs);
+    AttachShader(program, fs);
+    LinkProgram(program);
+    UseProgram(program);
+    Viewport(0, 0, 256, 256);
+
+    const float vertices[] = {
+        -0.5f, -0.5f,
+         0.5f, -0.5f,
+         0.0f,  0.5f,
+    };
+    GLuint vbo = 0;
+    GenBuffers(1, &vbo);
+    BindBuffer(GL_ARRAY_BUFFER, vbo);
+    BufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
+
+    GLuint vao = 0;
+    GenVertexArrays(1, &vao);
+    BindVertexArray(vao);
+    EnableVertexAttribArray(0);
+    VertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 0, nullptr);
+
+    Enable(GL_SCISSOR_TEST);
+    Scissor(96, 96, 64, 64);
+
+    DiligentBackend::BackendObject_Diligent backend;
+    backend.Initialize();
+    auto* renderer = backend.GetRenderer();
+    if (renderer == nullptr) {
+        GTEST_SKIP() << "No Vulkan adapter available; skipping scissor state test";
+    }
+
+    renderer->Clear(0.0f, 1.0f, 0.0f, 1.0f);
+    renderer->DrawFromState(GL_TRIANGLES, 0, 3, 0, nullptr);
+    renderer->Present();
+
+    std::uint8_t center[4] = {};
+    renderer->ReadPixels(128, 128, 1, 1, center);
+    EXPECT_GT(center[0], 200) << "center should be red inside scissor rect";
+    EXPECT_LT(center[1], 50) << "center should not be green";
+
+    std::uint8_t corner[4] = {};
+    renderer->ReadPixels(0, 0, 1, 1, corner);
+    EXPECT_GT(corner[1], 200) << "corner should remain green outside scissor rect";
+    EXPECT_LT(corner[0], 50) << "corner should not be red";
+}
+
+
+TEST(DiligentVulkanBackend, DrawsWithBlendFromMobileGLState) {
+    MobileGL::Initialize();
+
+    const char* vsSrc = R"(#version 330 core
+layout(location = 0) in vec2 Position;
+void main() { gl_Position = vec4(Position, 0.0, 1.0); }
+)";
+    const char* fsSrc = R"(#version 330 core
+out vec4 Color;
+void main() { Color = vec4(1.0, 0.0, 0.0, 0.5); }
+)";
+
+    const GLuint vs = CreateShader(GL_VERTEX_SHADER);
+    ShaderSource(vs, 1, &vsSrc, nullptr);
+    CompileShader(vs);
+    const GLuint fs = CreateShader(GL_FRAGMENT_SHADER);
+    ShaderSource(fs, 1, &fsSrc, nullptr);
+    CompileShader(fs);
+    const GLuint program = CreateProgram();
+    AttachShader(program, vs);
+    AttachShader(program, fs);
+    LinkProgram(program);
+    UseProgram(program);
+    Viewport(0, 0, 256, 256);
+
+    const float vertices[] = {
+        -0.5f, -0.5f,
+         0.5f, -0.5f,
+         0.0f,  0.5f,
+    };
+    GLuint vbo = 0;
+    GenBuffers(1, &vbo);
+    BindBuffer(GL_ARRAY_BUFFER, vbo);
+    BufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
+
+    GLuint vao = 0;
+    GenVertexArrays(1, &vao);
+    BindVertexArray(vao);
+    EnableVertexAttribArray(0);
+    VertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 0, nullptr);
+
+    Enable(GL_BLEND);
+    BlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+
+    DiligentBackend::BackendObject_Diligent backend;
+    backend.Initialize();
+    auto* renderer = backend.GetRenderer();
+    if (renderer == nullptr) {
+        GTEST_SKIP() << "No Vulkan adapter available; skipping blend state test";
+    }
+
+    renderer->Clear(0.0f, 1.0f, 0.0f, 1.0f);
+    renderer->DrawFromState(GL_TRIANGLES, 0, 3, 0, nullptr);
+    renderer->Present();
+
+    std::uint8_t center[4] = {};
+    renderer->ReadPixels(128, 128, 1, 1, center);
+    EXPECT_GT(center[0], 80) << "center should include blended red";
+    EXPECT_GT(center[1], 80) << "center should include remaining green";
+    EXPECT_LT(center[0], 220) << "center should not be pure red";
+    EXPECT_LT(center[1], 220) << "center should not be pure green";
+}