[Piglit] [PATCH] arb_viewport_array: add test for fractional viewport coordinates

[Józef Kucia]

In Direct3D 11, negative fractional viewport coordinates shift the
bottom right corner by a whole integer. Some OpenGL drivers seem to
implement Direct3D 11 behavior.

The test fails on i965 and Nvidia binary driver. It succeeds on
radeonsi.
---

The test exercises a bug in i965.

I don't have commit access.

---
 tests/opengl.py                                    |  1 +
 tests/spec/arb_viewport_array/CMakeLists.gl.txt    |  1 +
 .../spec/arb_viewport_array/fractional_viewport.c  | 94 ++++++++++++++++++++++
 3 files changed, 96 insertions(+)
 create mode 100644 tests/spec/arb_viewport_array/fractional_viewport.c

diff --git a/tests/opengl.py b/tests/opengl.py
index 347e8c5d4009..7605fe5d990d 100644
--- a/tests/opengl.py
+++ b/tests/opengl.py
@@ -2693,6 +2693,7 @@ with profile.test_list.group_manager(
     g(['arb_viewport_array-render-depthrange'], 'render-depthrange')
     g(['arb_viewport_array-render-scissor'], 'render-scissor')
     g(['arb_viewport_array-clear'], 'clear')
+    g(['arb_viewport_array-fractional-viewport'], 'fractional-viewport')
 
 with profile.test_list.group_manager(
         PiglitGLTest,
diff --git a/tests/spec/arb_viewport_array/CMakeLists.gl.txt b/tests/spec/arb_viewport_array/CMakeLists.gl.txt
index 85715774c674..5abb23d3e6bf 100644
--- a/tests/spec/arb_viewport_array/CMakeLists.gl.txt
+++ b/tests/spec/arb_viewport_array/CMakeLists.gl.txt
@@ -20,5 +20,6 @@ piglit_add_executable(arb_viewport_array-render-viewport render_viewport.c)
 piglit_add_executable(arb_viewport_array-render-viewport-2 render_viewport_2.c)
 piglit_add_executable(arb_viewport_array-render-depthrange render_depthrange.c)
 piglit_add_executable(arb_viewport_array-render-scissor render_scissor.c)
+piglit_add_executable(arb_viewport_array-fractional-viewport fractional_viewport.c)
 
 # vim: ft=cmake:
diff --git a/tests/spec/arb_viewport_array/fractional_viewport.c b/tests/spec/arb_viewport_array/fractional_viewport.c
new file mode 100644
index 000000000000..1c4a9da941f2
--- /dev/null
+++ b/tests/spec/arb_viewport_array/fractional_viewport.c
@@ -0,0 +1,94 @@
+/*
+ * Copyright (c) 2018 Józef Kucia <joseph.kucia at gmail.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ */
+
+/**
+ * Tests rendering with negative fractional viewport coordinates.
+ */
+#include "piglit-util-gl.h"
+
+PIGLIT_GL_TEST_CONFIG_BEGIN
+
+	config.supports_gl_compat_version = 33;
+	config.supports_gl_core_version = 33;
+
+	config.window_visual = PIGLIT_GL_VISUAL_RGBA | PIGLIT_GL_VISUAL_DOUBLE;
+	config.khr_no_error_support = PIGLIT_NO_ERRORS;
+
+PIGLIT_GL_TEST_CONFIG_END
+
+static const char *vs =
+	"#version 150\n"
+	"in vec4 piglit_vertex;\n"
+	"void main() { \n"
+	"	gl_Position = piglit_vertex;\n"
+	"}\n";
+
+static const char *fs =
+	"#version 150\n"
+	"out vec4 color;\n"
+	"void main() {\n"
+	"	color = uvec4(0.0f, 1.0f, 0.0f, 1.0f);\n"
+	"}\n";
+
+static bool
+draw_fractional_viewport(void)
+{
+	static const float green[] = {0.0f, 1.0f, 0.0f, 1.0f};
+
+	glViewport(0, 0, piglit_width, piglit_height); /* for glClear() */
+	glClear(GL_COLOR_BUFFER_BIT);
+
+	glViewportIndexedf(0, -0.4f, -0.4f, piglit_width, piglit_height);
+	piglit_draw_rect(-1, -1, 2, 2);
+	return piglit_probe_rect_rgba(0, 0, piglit_width, piglit_height, green);
+}
+
+enum piglit_result
+piglit_display(void)
+{
+	bool pass = true;
+
+	pass = draw_fractional_viewport();
+	pass = piglit_check_gl_error(GL_NO_ERROR) && pass;
+	piglit_present_results();
+	return pass ? PIGLIT_PASS : PIGLIT_FAIL;
+}
+
+void
+piglit_init(int argc, char **argv)
+{
+	GLuint program;
+	GLuint vao;
+
+	piglit_require_extension("GL_ARB_viewport_array");
+
+	program = piglit_build_simple_program_multiple_shaders(
+					GL_VERTEX_SHADER, vs,
+					GL_FRAGMENT_SHADER, fs,
+					0);
+	glUseProgram(program);
+
+	glGenVertexArrays(1, &vao);
+	glBindVertexArray(vao);
+}
-- 
2.16.1