[Piglit] [PATCH] Transform feedback: test buffer size change after binding.

Paul Berry stereotype441 at gmail.com
Mon Dec 17 10:17:51 PST 2012


---
 tests/all.tests                                    |   6 +
 .../spec/ext_transform_feedback/CMakeLists.gl.txt  |   1 +
 tests/spec/ext_transform_feedback/change-size.c    | 320 +++++++++++++++++++++
 3 files changed, 327 insertions(+)
 create mode 100644 tests/spec/ext_transform_feedback/change-size.c

diff --git a/tests/all.tests b/tests/all.tests
index c823bcf..1cbbe98 100644
--- a/tests/all.tests
+++ b/tests/all.tests
@@ -1925,6 +1925,12 @@ for mode in ['discard', 'buffer', 'prims_generated', 'prims_written']:
         ext_transform_feedback[test_name] = concurrent_test(
                 'ext_transform_feedback-{0}'.format(test_name))
 
+for test_case in ['base-shrink', 'base-grow', 'offset-shrink', 'offset-grow',
+                  'range-shrink', 'range-grow']:
+        test_name = 'change-size {0}'.format(test_case)
+        ext_transform_feedback[test_name] = concurrent_test(
+                'ext_transform_feedback-{0}'.format(test_name))
+
 arb_transform_feedback2 = Group()
 spec['ARB_transform_feedback2'] = arb_transform_feedback2
 arb_transform_feedback2['draw-auto'] = PlainExecTest(['arb_transform_feedback2-draw-auto', '-auto'])
diff --git a/tests/spec/ext_transform_feedback/CMakeLists.gl.txt b/tests/spec/ext_transform_feedback/CMakeLists.gl.txt
index 9325091..63c3f4b 100644
--- a/tests/spec/ext_transform_feedback/CMakeLists.gl.txt
+++ b/tests/spec/ext_transform_feedback/CMakeLists.gl.txt
@@ -13,6 +13,7 @@ piglit_add_executable (ext_transform_feedback-alignment alignment.c)
 piglit_add_executable (ext_transform_feedback-api-errors api-errors.c)
 piglit_add_executable (ext_transform_feedback-buffer-usage buffer-usage.c)
 piglit_add_executable (ext_transform_feedback-builtin-varyings builtin-varyings.c)
+piglit_add_executable (ext_transform_feedback-change-size change-size.c)
 piglit_add_executable (ext_transform_feedback-discard-api discard-api.c)
 piglit_add_executable (ext_transform_feedback-discard-bitmap discard-bitmap.c)
 piglit_add_executable (ext_transform_feedback-discard-clear discard-clear.c)
diff --git a/tests/spec/ext_transform_feedback/change-size.c b/tests/spec/ext_transform_feedback/change-size.c
new file mode 100644
index 0000000..ea6fe46
--- /dev/null
+++ b/tests/spec/ext_transform_feedback/change-size.c
@@ -0,0 +1,320 @@
+/*
+ * Copyright © 2012 Intel Corporation
+ *
+ * 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 change-size.c
+ *
+ * Confirm that transform feedback properly handles a change in the
+ * size of a transform feedback buffer after it is bound but before it
+ * is used.
+ *
+ * In particular, this test verifies the following behaviours, from
+ * the GL 4.3 spec, section 6.1.1 ("Binding Buffer Objects to Indexed
+ * Targets"):
+ *
+ *   BindBufferBase binds the entire buffer, even when the size of the buffer
+ *   is changed after the binding is established. It is equivalent to calling
+ *   BindBufferRange with offset zero, while size is determined by the size of
+ *   the bound buffer at the time the binding is used.
+ *
+ *   Regardless of the size specified with BindBufferRange, or indirectly with
+ *   BindBufferBase, the GL will never read or write beyond the end of a bound
+ *   buffer. In some cases this constraint may result in visibly different
+ *   behavior when a buffer overflow would otherwise result, such as described
+ *   for transform feedback operations in section 13.2.2.
+ *
+ * This test verifies that the expected number of primitives are
+ * written after a change to the size of the transform feedback
+ * buffer, using both a GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN query
+ * and by looking at the contents of the buffer itself.  We run
+ * transform feedback in GL_TRIANGLES mode and use a buffer size that
+ * is not a multiple of 3, so that we can look at the last element in
+ * the transform feedback buffer and verify that transform feedback
+ * didn't overwrite it.
+ *
+ * The test performs the following operations:
+ *
+ * 1. Create a transform feedback buffer using glBufferData().
+ *
+ * 2. Bind the buffer for transform feedback using either
+ *    glBindBufferBase, glBindBufferRange, or glBindBufferOffsetEXT
+ *    (if supported).
+ *
+ * 3. Change the size of the bound buffer using glBufferData().  A
+ *    non-null data pointer is passed to glBufferData() to store a
+ *    known pattern in the buffer, so that in step 6 we'll be able to
+ *    determine which parts of the buffer were overwritten.
+ *
+ * 4. Draw some triangles, feeding back a single float from each
+ *    vertex.
+ *
+ * 5. Verify, using a GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN query,
+ *    that the expected number of primitives were written to the
+ *    buffer.
+ *
+ * 6. Verify, using glMapBuffer, that the expected data was written to
+ *    the buffer.
+ */
+
+#include "piglit-util-gl-common.h"
+
+PIGLIT_GL_TEST_CONFIG_BEGIN
+
+	config.supports_gl_compat_version = 10;
+
+	config.window_visual = PIGLIT_GL_VISUAL_DOUBLE | PIGLIT_GL_VISUAL_RGB | PIGLIT_GL_VISUAL_ALPHA;
+
+PIGLIT_GL_TEST_CONFIG_END
+
+/**
+ * Maximum buffer size--used for declaraing static arrays.  Measured
+ * in multiples of sizeof(GLfloat).
+ */
+#define MAX_BUFFER_SIZE_FLOATS 10
+
+static GLuint prog;
+static GLuint xfb_buf;
+static GLuint query;
+
+const struct test_case
+{
+	/**
+	 * Name of the test case.  NULL is used as a sentinel to mark
+	 * the end of the list of test cases.
+	 */
+	const char *name;
+
+	/**
+	 * Size that the buffer should have before binding.  Measured
+	 * in multiples of sizeof(GLfloat).
+	 */
+	unsigned initial_size;
+
+	/**
+	 * Offset to pass to glBindBufferRange/glBindBufferOffsetEXT,
+	 * or zero if glBindBufferBase should be used.  Measured in
+	 * multiples of sizeof(GLfloat).
+	 */
+	unsigned bind_offset;
+
+	/**
+	 * Size to pass to glBindBufferRange, or zero if
+	 * glBindBufferOffsetEXT/glBindBufferBase should be used.
+	 * Measured in multiples of sizeof(GLfloat).
+	 */
+	unsigned bind_size;
+
+	/**
+	 * Size of the buffer that should be passed to
+	 * glBindBufferData after the buffer is bound.  Measured in
+	 * multiples of sizeof(GLfloat).
+	 */
+	unsigned new_size;
+
+	/**
+	 * Number of triangles to draw.
+	 */
+	unsigned num_draw_triangles;
+
+	/**
+	 * Number of primitives that are expected to be written to the
+	 * buffer.
+	 */
+	unsigned num_feedback_triangles;
+} test_cases[] = {
+	/* name            initial  bind    bind  new   num tris:
+	 *                 size     offset  size  size  draw  feedback */
+	{ "base-shrink",   7,       0,      0,    4,    2,    1 },
+	{ "base-grow",     4,       0,      0,    7,    2,    2 },
+	{ "offset-shrink", 10,      3,      0,    7,    2,    1 },
+	{ "offset-grow",   7,       3,      0,    10,   2,    2 },
+	{ "range-shrink",  10,      3,      7,    7,    2,    1 },
+	{ "range-grow",    7,       3,      4,    10,   2,    1 },
+	{ NULL,            0,       0,      0,    0,    0,    0 }
+};
+
+const struct test_case *selected_test;
+
+/**
+ * Vertex shader, which simply copies its input attribute to its
+ * output varying, adding 100 in the process.
+ */
+static const char *vstext =
+	"#version 120\n"
+	"attribute float input_value;\n"
+	"varying float output_value;\n"
+	"\n"
+	"void main()\n"
+	"{\n"
+	"  gl_Position = vec4(0.0);\n"
+	"  output_value = 100.0 + input_value;\n"
+	"}\n";
+
+static void
+print_usage_and_exit(const char *prog_name)
+{
+	unsigned i;
+	printf("Usage: %s <test_case>\n"
+	       "  where <test_case> is one of the following:\n", prog_name);
+	for (i = 0; test_cases[i].name != NULL; i++)
+		printf("    %s\n", test_cases[i].name);
+	exit(1);
+}
+
+static const struct test_case *
+interpret_test_case_arg(const char *arg)
+{
+	unsigned i;
+	for (i = 0; test_cases[i].name != NULL; i++) {
+		if (strcmp(test_cases[i].name, arg) == 0)
+			return &test_cases[i];
+	}
+	return NULL;
+}
+
+void
+piglit_init(int argc, char **argv)
+{
+	GLuint vs;
+	const char *varying_name = "output_value";
+
+	/* Parse args */
+	if (argc != 2)
+		print_usage_and_exit(argv[0]);
+	selected_test = interpret_test_case_arg(argv[1]);
+	if (selected_test == NULL)
+		print_usage_and_exit(argv[0]);
+
+	/* Make sure required GL features are present */
+	piglit_require_GLSL_version(120);
+	piglit_require_transform_feedback();
+	if (selected_test->bind_offset != 0 && selected_test->bind_size == 0) {
+		/* Test requires glBindBufferOffsetEXT, which is in
+		 * EXT_transform_feedback, but was never adopted into
+		 * OpenGL.
+		 */
+		piglit_require_extension("GL_EXT_transform_feedback");
+	}
+
+	/* Create program and buffer */
+	vs = piglit_compile_shader_text(GL_VERTEX_SHADER, vstext);
+	prog = glCreateProgram();
+	glAttachShader(prog, vs);
+	glTransformFeedbackVaryings(prog, 1, &varying_name,
+				    GL_INTERLEAVED_ATTRIBS);
+	glLinkProgram(prog);
+	if (!piglit_link_check_status(prog))
+		piglit_report_result(PIGLIT_FAIL);
+	glGenBuffers(1, &xfb_buf);
+	glGenQueries(1, &query);
+	if (!piglit_check_gl_error(GL_NO_ERROR))
+		piglit_report_result(PIGLIT_FAIL);
+}
+
+enum piglit_result
+piglit_display(void)
+{
+	GLint input_index = glGetAttribLocation(prog, "input_value");
+	GLfloat canary_data[MAX_BUFFER_SIZE_FLOATS];
+	GLfloat input_data[MAX_BUFFER_SIZE_FLOATS];
+	GLfloat expected_data[MAX_BUFFER_SIZE_FLOATS];
+	GLfloat *output_data;
+	GLuint query_result;
+	GLboolean pass = GL_TRUE;
+	unsigned i;
+
+	glUseProgram(prog);
+
+	/* Create a transform feedback buffer. */
+	glBindBuffer(GL_TRANSFORM_FEEDBACK_BUFFER, xfb_buf);
+	glBufferData(GL_TRANSFORM_FEEDBACK_BUFFER,
+		     selected_test->initial_size * sizeof(GLfloat), NULL,
+		     GL_STREAM_READ);
+
+	/* Bind the buffer for transform feedback. */
+	if (selected_test->bind_size != 0) {
+		glBindBufferRange(GL_TRANSFORM_FEEDBACK_BUFFER, 0, xfb_buf,
+				  selected_test->bind_offset * sizeof(GLfloat),
+				  selected_test->bind_size * sizeof(GLfloat));
+	} else if (selected_test->bind_offset != 0) {
+		glBindBufferOffsetEXT(GL_TRANSFORM_FEEDBACK_BUFFER, 0,
+				      xfb_buf,
+				      selected_test->bind_offset
+				      * sizeof(GLfloat));
+	} else {
+		glBindBufferBase(GL_TRANSFORM_FEEDBACK_BUFFER, 0, xfb_buf);
+	}
+
+	/* Change the size of the bound buffer. */
+	for (i = 0; i < MAX_BUFFER_SIZE_FLOATS; i++)
+		canary_data[i] = -1;
+	glBufferData(GL_TRANSFORM_FEEDBACK_BUFFER,
+		     selected_test->new_size * sizeof(GLfloat), canary_data,
+		     GL_STREAM_READ);
+
+	/* Draw some triangles. */
+	for (i = 0; i < MAX_BUFFER_SIZE_FLOATS; i++)
+		input_data[i] = i + 1;
+	glBindBuffer(GL_ARRAY_BUFFER, 0);
+	glVertexAttribPointer(input_index, 1, GL_FLOAT, GL_FALSE,
+			      sizeof(GLfloat), input_data);
+	glEnableVertexAttribArray(input_index);
+	glBeginTransformFeedback(GL_TRIANGLES);
+	glBeginQuery(GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN, query);
+	glDrawArrays(GL_TRIANGLES, 0, selected_test->num_draw_triangles * 3);
+	glEndQuery(GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN);
+	glEndTransformFeedback();
+
+	/* Verify that the expected number of primitives were
+	 * written.
+	 */
+	glGetQueryObjectuiv(query, GL_QUERY_RESULT, &query_result);
+	printf("PRIMITIVES_WRITTEN: expected=%u, actual=%u\n",
+	       selected_test->num_feedback_triangles, query_result);
+	if (query_result != selected_test->num_feedback_triangles)
+		pass = GL_FALSE;
+
+	/* Verify that the expected data was written. */
+	for (i = 0; i < selected_test->new_size; i++) {
+		if (i >= selected_test->bind_offset &&
+		    i < (3 * selected_test->num_feedback_triangles
+			 + selected_test->bind_offset)) {
+			expected_data[i] = 100.0
+				+ input_data[i - selected_test->bind_offset];
+		} else {
+			expected_data[i] = canary_data[i];
+		}
+	}
+	output_data = glMapBuffer(GL_TRANSFORM_FEEDBACK_BUFFER, GL_READ_ONLY);
+	for (i = 0; i < selected_test->new_size; ++i) {
+		printf("data[%u]: expected=%f, actual=%f\n", i,
+		       expected_data[i], output_data[i]);
+		if (expected_data[i] != output_data[i])
+			pass = GL_FALSE;
+	}
+	glUnmapBuffer(GL_TRANSFORM_FEEDBACK_BUFFER);
+
+	piglit_present_results();
+
+	return pass ? PIGLIT_PASS : PIGLIT_FAIL;
+}
-- 
1.8.0.2



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