ext_polygon_offset_clamp: add simple draw test

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Glenn Kennard <glenn.kennard@gmail.com>
Reviewed-by: Chris Forbes <chrisf@ijw.co.nz>

6 files changed, 336 insertions, 0 deletions

diff --git a/tests/all.py b/tests/all.py
index d6f4ac3b9..1b35ec7b6 100644
--- a/tests/all.py
+++ b/tests/all.py
@@ -3759,6 +3759,11 @@ arb_compute_shader['built-in constants'] = PiglitGLTest(
      os.path.join(TESTS_DIR, 'spec', 'arb_compute_shader', 'minimum-maximums.txt')],
     run_concurrent=True)
 
+ext_polygon_offset_clamp = {}
+spec['EXT_polygon_offset_clamp'] = ext_polygon_offset_clamp
+add_concurrent_test(ext_polygon_offset_clamp, ['ext_polygon_offset_clamp-draw'])
+add_concurrent_test(ext_polygon_offset_clamp, ['ext_polygon_offset_clamp-dlist'])
+
 # group glslparsertest ------------------------------------------------------
 glslparsertest = {}
 # Add all shader source files in the directories below.
diff --git a/tests/spec/CMakeLists.txt b/tests/spec/CMakeLists.txt
index 890b1d299..ed8000592 100644
--- a/tests/spec/CMakeLists.txt
+++ b/tests/spec/CMakeLists.txt
@@ -117,3 +117,4 @@ add_subdirectory (ext_unpack_subimage)
 add_subdirectory (arb_vertex_array_object)
 add_subdirectory (oes_texture_float)
 add_subdirectory (arb_direct_state_access)
+add_subdirectory (ext_polygon_offset_clamp)
diff --git a/tests/spec/ext_polygon_offset_clamp/CMakeLists.gl.txt b/tests/spec/ext_polygon_offset_clamp/CMakeLists.gl.txt
new file mode 100644
index 000000000..db6824942
--- /dev/null
+++ b/tests/spec/ext_polygon_offset_clamp/CMakeLists.gl.txt
@@ -0,0 +1,14 @@
+include_directories(
+	${GLEXT_INCLUDE_DIR}
+	${OPENGL_INCLUDE_PATH}
+)
+
+link_libraries (
+	piglitutil_${piglit_target_api}
+	${OPENGL_gl_LIBRARY}
+)
+
+piglit_add_executable (ext_polygon_offset_clamp-draw draw.c)
+piglit_add_executable (ext_polygon_offset_clamp-dlist dlist.c)
+
+# vim: ft=cmake:
diff --git a/tests/spec/ext_polygon_offset_clamp/CMakeLists.txt b/tests/spec/ext_polygon_offset_clamp/CMakeLists.txt
new file mode 100644
index 000000000..144a306f4
--- /dev/null
+++ b/tests/spec/ext_polygon_offset_clamp/CMakeLists.txt
@@ -0,0 +1 @@
+piglit_include_target_api()
diff --git a/tests/spec/ext_polygon_offset_clamp/dlist.c b/tests/spec/ext_polygon_offset_clamp/dlist.c
new file mode 100644
index 000000000..868621667
--- /dev/null
+++ b/tests/spec/ext_polygon_offset_clamp/dlist.c
@@ -0,0 +1,145 @@
+/*
+ * Copyright (C) 2015 Ilia Mirkin
+ *
+ * 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.
+ */
+
+/**
+ * \file dlist.c
+ *
+ * Test that glPolygonOffsetClampEXT works inside of a call list. See
+ * draw.c for testing technique comments.
+ */
+
+#include "piglit-util-gl.h"
+
+PIGLIT_GL_TEST_CONFIG_BEGIN
+
+	config.supports_gl_compat_version = 21;
+	config.window_visual = PIGLIT_GL_VISUAL_RGB | PIGLIT_GL_VISUAL_DEPTH | PIGLIT_GL_VISUAL_DOUBLE;
+
+PIGLIT_GL_TEST_CONFIG_END
+
+GLint prog, color;
+
+enum piglit_result
+piglit_display(void)
+{
+	static const float blue[4] = {0, 0, 1, 1};
+	static const float red[4] = {1, 0, 0, 1};
+	static const float green[4] = {0, 1, 0, 1};
+
+	GLuint list;
+	bool passa = true, passb = true;
+
+	glUseProgram(prog);
+
+	glViewport(0, 0, piglit_width, piglit_height);
+	glEnable(GL_DEPTH_TEST);
+	glEnable(GL_POLYGON_OFFSET_FILL);
+
+	glClearColor(0, 0, 1, 1);
+	glClearDepth(0.5);
+	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+	list = glGenLists(2);
+
+	/* Draw red rectangle that slopes between 1 and 0.1. Use a
+	 * polygon offset with a high factor but small clamp
+	 */
+	glNewList(list, GL_COMPILE_AND_EXECUTE);
+	glPolygonOffsetClampEXT(-1000, 0, -0.05);
+	glUniform4fv(color, 1, red);
+	glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
+	glEndList();
+
+	if (!piglit_probe_rect_rgba(0, 0, piglit_width, piglit_height, blue)) {
+		printf("  FAIL: red rect peeks over blue rect\n");
+		passa = false;
+	}
+
+	/* And now set the clamp such that all parts of the polygon
+	 * can pass the depth test.
+	 */
+	glNewList(list + 1, GL_COMPILE_AND_EXECUTE);
+	glPolygonOffsetClampEXT(-1000, 0, -0.51);
+	glUniform4fv(color, 1, green);
+	glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
+	glEndList();
+
+	if (!piglit_probe_rect_rgba(0, 0, piglit_width, piglit_height, green)) {
+		printf("  FAIL: green rect does not cover blue rect\n");
+		passa = false;
+	}
+
+	piglit_report_subtest_result(passa ? PIGLIT_PASS : PIGLIT_FAIL,
+				     "compile and execute");
+	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+	glCallList(list);
+	if (!piglit_probe_rect_rgba(0, 0, piglit_width, piglit_height, blue)) {
+		printf("  FAIL: red rect peeks over blue rect\n");
+		passb = false;
+	}
+
+	glCallList(list + 1);
+	if (!piglit_probe_rect_rgba(0, 0, piglit_width, piglit_height, green)) {
+		printf("  FAIL: green rect does not cover blue rect\n");
+		passb = false;
+	}
+
+	piglit_report_subtest_result(passb ? PIGLIT_PASS : PIGLIT_FAIL,
+				     "call");
+
+	piglit_present_results();
+
+	return (passa && passb) ? PIGLIT_PASS : PIGLIT_FAIL;
+}
+
+void
+piglit_init(int argc, char **argv)
+{
+	static const float verts[4][4] = {
+		/* x   y   z   w */
+		{ -1, -1, 1.0, 1 },
+		{  1, -1, 1.0, 1 },
+		{ -1,  1, 0.1, 1 },
+		{  1,  1, 0.1, 1 }
+	};
+
+	GLuint bo;
+
+	piglit_require_extension("GL_EXT_polygon_offset_clamp");
+
+	prog = piglit_build_simple_program(
+			"#version 120\n"
+			"void main() { gl_Position = gl_Vertex; }\n",
+
+			"#version 120\n"
+			"uniform vec4 color;\n"
+			"void main() { gl_FragColor = color; }\n");
+	color = glGetUniformLocation(prog, "color");
+
+	glEnableVertexAttribArray(0);
+	glGenBuffers(1, &bo);
+	glBindBuffer(GL_ARRAY_BUFFER, bo);
+	glBufferData(GL_ARRAY_BUFFER, sizeof(verts), verts, GL_STATIC_DRAW);
+	glVertexAttribPointer(0, 4, GL_FLOAT, GL_FALSE, 0, (GLvoid const *)0);
+}
diff --git a/tests/spec/ext_polygon_offset_clamp/draw.c b/tests/spec/ext_polygon_offset_clamp/draw.c
new file mode 100644
index 000000000..f17cfb8e5
--- /dev/null
+++ b/tests/spec/ext_polygon_offset_clamp/draw.c
@@ -0,0 +1,170 @@
+/*
+ * Copyright (C) 2015 Ilia Mirkin
+ *
+ * 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.
+ */
+
+/**
+ * \file draw.c
+ *
+ * Test that GL_EXT_polygon_offset_clamp actually applies the
+ * clamp. The polygon is set up between z = 1 and z = 0.1 (so under
+ * depth = 0.5).
+ *
+ * 1. Clear the depth buffer to 0.5 (leaving the depth func as LESS)
+ * 2. Draw the polygon with red, clamping the offset to -0.05. This
+ *    ensures that even the z=0.1 end (i.e. depth = 0.55) does not go
+ *    below the value in the depth buffer.
+ * 3. Draw the polygon again with green, clamping the offset at -0.51,
+ *    ensuring that every point of the polygon can end up being offset to
+ *    a depth value below 0.5.
+ */
+
+#include "piglit-util-gl.h"
+
+PIGLIT_GL_TEST_CONFIG_BEGIN
+
+	config.supports_gl_compat_version = 21;
+	config.window_visual = PIGLIT_GL_VISUAL_RGB | PIGLIT_GL_VISUAL_DEPTH | PIGLIT_GL_VISUAL_DOUBLE;
+
+PIGLIT_GL_TEST_CONFIG_END
+
+GLint prog, color, zflip;
+
+enum piglit_result
+piglit_display(void)
+{
+	static const float blue[4] = {0, 0, 1, 1};
+	static const float red[4] = {1, 0, 0, 1};
+	static const float green[4] = {0, 1, 0, 1};
+
+	bool passa = true, passb = true;
+
+	glUseProgram(prog);
+
+	glViewport(0, 0, piglit_width, piglit_height);
+	glEnable(GL_DEPTH_TEST);
+	glEnable(GL_POLYGON_OFFSET_FILL);
+
+	glUniform1f(zflip, 1.0);
+	glClearColor(0, 0, 1, 1);
+	glClearDepth(0.5);
+	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+	/* NOTE: It appears that at least nvidia hw will end up
+	 * wrapping around if the final z value goes below 0 (or
+	 * something). This can come up when testing without the
+	 * clamp.
+	 */
+
+	/* Draw red rectangle that slopes between 1 and 0.1. Use a
+	 * polygon offset with a high factor but small clamp
+	 */
+	glPolygonOffsetClampEXT(-1000, 0, -0.05);
+	glUniform4fv(color, 1, red);
+	glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
+	if (!piglit_probe_rect_rgba(0, 0, piglit_width, piglit_height, blue)) {
+		printf("  FAIL: red rect peeks over blue rect\n");
+		passa = false;
+	}
+
+	/* And now set the clamp such that all parts of the polygon
+	 * can pass the depth test.
+	 */
+	glPolygonOffsetClampEXT(-1000, 0, -0.51);
+	glUniform4fv(color, 1, green);
+	glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
+	if (!piglit_probe_rect_rgba(0, 0, piglit_width, piglit_height, green)) {
+		printf("  FAIL: green rect does not cover blue rect\n");
+		passa = false;
+	}
+
+	piglit_report_subtest_result(passa ? PIGLIT_PASS : PIGLIT_FAIL,
+				     "negative clamp");
+
+	/* Now try this again with the inverse approach and a positive
+	 * clamp value. The polygon will now slope between -1 and
+	 * -0.1. Everything is reversed, so just negate all the
+	 * previous values.
+	 */
+
+	glUniform1f(zflip, -1.0);
+	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+	glDepthFunc(GL_GREATER);
+
+	glPolygonOffsetClampEXT(1000, 0, 0.05);
+	glUniform4fv(color, 1, red);
+	glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
+	if (!piglit_probe_rect_rgba(0, 0, piglit_width, piglit_height, blue)) {
+		printf("  FAIL: red rect peeks over blue rect\n");
+		passb = false;
+	}
+
+	/* And now set the clamp so that all parts of the polygon pass
+	 * the depth test.
+	 */
+	glPolygonOffsetClampEXT(1000, 0, 0.51);
+	glUniform4fv(color, 1, green);
+	glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
+	if (!piglit_probe_rect_rgba(0, 0, piglit_width, piglit_height, green)) {
+		printf("  FAIL: green rect does not cover blue rect\n");
+		passb = false;
+	}
+
+	piglit_report_subtest_result(passb ? PIGLIT_PASS : PIGLIT_FAIL,
+				     "positive clamp");
+
+	piglit_present_results();
+
+	return (passa && passb) ? PIGLIT_PASS : PIGLIT_FAIL;
+}
+
+void
+piglit_init(int argc, char **argv)
+{
+	static const float verts[4][4] = {
+		/* x   y   z   w */
+		{ -1, -1, 1.0, 1 },
+		{  1, -1, 1.0, 1 },
+		{ -1,  1, 0.1, 1 },
+		{  1,  1, 0.1, 1 }
+	};
+
+	GLuint bo;
+
+	piglit_require_extension("GL_EXT_polygon_offset_clamp");
+
+	prog = piglit_build_simple_program(
+			"#version 120\n"
+			"uniform float zflip;\n"
+			"void main() { gl_Position = gl_Vertex * vec4(1, 1, zflip, 1); }\n",
+
+			"#version 120\n"
+			"uniform vec4 color;\n"
+			"void main() { gl_FragColor = color; }\n");
+	color = glGetUniformLocation(prog, "color");
+	zflip = glGetUniformLocation(prog, "zflip");
+
+	glEnableVertexAttribArray(0);
+	glGenBuffers(1, &bo);
+	glBindBuffer(GL_ARRAY_BUFFER, bo);
+	glBufferData(GL_ARRAY_BUFFER, sizeof(verts), verts, GL_STATIC_DRAW);
+	glVertexAttribPointer(0, 4, GL_FLOAT, GL_FALSE, 0, (GLvoid const *)0);
+}