[Piglit] [PATCH] Transform feedback: immediately reuse XFB output as vertex input.
Paul Berry
stereotype441 at gmail.com
Thu Dec 22 14:03:17 PST 2011
This test verifies that transform feedback data is properly handled if
it is immediately re-used as vertex input, with as little change as
possible to GL state in between. This verifies that the
implementation maintains proper cache coherency between transform
feedback outputs and vertex inputs.
Verified on the nVidia proprietary Linux driver.
---
tests/all.tests | 1 +
.../spec/ext_transform_feedback/CMakeLists.gl.txt | 1 +
.../spec/ext_transform_feedback/immediate-reuse.c | 165 ++++++++++++++++++++
3 files changed, 167 insertions(+), 0 deletions(-)
create mode 100644 tests/spec/ext_transform_feedback/immediate-reuse.c
diff --git a/tests/all.tests b/tests/all.tests
index 0390cbc..5ec532e 100644
--- a/tests/all.tests
+++ b/tests/all.tests
@@ -1381,6 +1381,7 @@ ext_transform_feedback['discard-clear'] = concurrent_test('ext_transform_feedbac
ext_transform_feedback['discard-copypixels'] = concurrent_test('ext_transform_feedback-discard-copypixels')
ext_transform_feedback['discard-drawarrays'] = concurrent_test('ext_transform_feedback-discard-drawarrays')
ext_transform_feedback['discard-drawpixels'] = concurrent_test('ext_transform_feedback-discard-drawpixels')
+ext_transform_feedback['immediate-reuse'] = concurrent_test('ext_transform_feedback-immediate-reuse')
ext_transform_feedback['position-readback-bufferbase'] = PlainExecTest(['ext_transform_feedback-position', '-auto'])
ext_transform_feedback['position-readback-bufferbase-discard'] = PlainExecTest(['ext_transform_feedback-position', '-auto', 'discard'])
ext_transform_feedback['position-readback-bufferoffset'] = PlainExecTest(['ext_transform_feedback-position', '-auto', 'offset'])
diff --git a/tests/spec/ext_transform_feedback/CMakeLists.gl.txt b/tests/spec/ext_transform_feedback/CMakeLists.gl.txt
index ce8aa88..8582ef0 100644
--- a/tests/spec/ext_transform_feedback/CMakeLists.gl.txt
+++ b/tests/spec/ext_transform_feedback/CMakeLists.gl.txt
@@ -21,6 +21,7 @@ add_executable (ext_transform_feedback-discard-drawarrays discard-drawarrays.c)
add_executable (ext_transform_feedback-discard-drawpixels discard-drawpixels.c)
add_executable (ext_transform_feedback-generatemipmap generatemipmap.c)
add_executable (ext_transform_feedback-position position.c)
+add_executable (ext_transform_feedback-immediate-reuse immediate-reuse.c)
add_executable (ext_transform_feedback-interleaved interleaved.c)
add_executable (ext_transform_feedback-separate separate.c)
add_executable (ext_transform_feedback-output-type output-type.c)
diff --git a/tests/spec/ext_transform_feedback/immediate-reuse.c b/tests/spec/ext_transform_feedback/immediate-reuse.c
new file mode 100644
index 0000000..dd3c9cd
--- /dev/null
+++ b/tests/spec/ext_transform_feedback/immediate-reuse.c
@@ -0,0 +1,165 @@
+/*
+ * Copyright © 2011 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 immediate-reuse.c
+ *
+ * Verify that if a transform feedback output buffer is immediately
+ * re-used as a transform feedback input (changing no GL settings
+ * except for buffer bindings), rendering is correct.
+ *
+ * The test operates by using a shader whose transform feedback
+ * outputs are the same as its inputs, except with positions and
+ * colors offset by a constant value. It draws a pair of triangles on
+ * the left side of the screen, then cycles the transform feedback
+ * output back through as vertex input 15 times; this should result in
+ * a stepped gradient being drawn.
+ */
+
+#include "piglit-util.h"
+
+int piglit_width = 256;
+int piglit_height = 16;
+int piglit_window_mode = GLUT_DOUBLE | GLUT_RGB;
+
+static const char *vstext =
+ "attribute vec4 in_position;\n"
+ "attribute vec4 in_color;\n"
+ "varying vec4 xfb_position;\n"
+ "varying vec4 xfb_color;\n"
+ "varying vec4 out_color;\n"
+ "\n"
+ "void main()\n"
+ "{\n"
+ " gl_Position = in_position;\n"
+ " out_color = in_color;\n"
+ " xfb_position = in_position + vec4(0.125, 0.0, 0.0, 0.0);\n"
+ " xfb_color = in_color + vec4(0.0625, -0.0625, 0.0625, 0.0);\n"
+ "}\n";
+
+static const char *fstext =
+ "varying vec4 out_color;\n"
+ "\n"
+ "void main()\n"
+ "{\n"
+ " gl_FragColor = out_color;\n"
+ "}\n";
+
+static const char *varyings[] = { "xfb_position", "xfb_color" };
+
+static GLuint bufs[2];
+static GLuint prog;
+
+void
+piglit_init(int argc, char **argv)
+{
+ GLuint vs, fs;
+
+ piglit_require_GLSL();
+ piglit_require_transform_feedback();
+
+ vs = piglit_compile_shader_text(GL_VERTEX_SHADER, vstext);
+ fs = piglit_compile_shader_text(GL_FRAGMENT_SHADER, fstext);
+ prog = piglit_CreateProgram();
+ piglit_AttachShader(prog, vs);
+ piglit_AttachShader(prog, fs);
+ piglit_BindAttribLocation(prog, 0, "in_position");
+ piglit_BindAttribLocation(prog, 1, "in_color");
+ piglit_TransformFeedbackVaryings(prog, 2, varyings, GL_INTERLEAVED_ATTRIBS);
+ piglit_LinkProgram(prog);
+ if (!piglit_link_check_status(prog)) {
+ piglit_DeleteProgram(prog);
+ piglit_report_result(PIGLIT_FAIL);
+ }
+
+ glGenBuffers(2, bufs);
+}
+
+enum piglit_result
+piglit_display(void)
+{
+ int i;
+ GLboolean pass = GL_TRUE;
+ static const float initial_vertex_data[6][8] = {
+ /* position XYZW color RGBA */
+ { -1.0, -1.0, 0.0, 1.0, 0.0, 1.0, 0.0, 1.0 },
+ { -0.875, -1.0, 0.0, 1.0, 0.0, 1.0, 0.0, 1.0 },
+ { -1.0, 1.0, 0.0, 1.0, 0.0, 1.0, 0.0, 1.0 },
+ { -0.875, -1.0, 0.0, 1.0, 0.0, 1.0, 0.0, 1.0 },
+ { -0.875, 1.0, 0.0, 1.0, 0.0, 1.0, 0.0, 1.0 },
+ { -1.0, 1.0, 0.0, 1.0, 0.0, 1.0, 0.0, 1.0 }
+ };
+ static const float initial_dummy_data[6][8] = {
+ /* position XYZW color RGBA */
+ { -1.0, -1.0, 0.0, 1.0, 1.0, 0.0, 0.0, 1.0 },
+ { -0.875, -1.0, 0.0, 1.0, 1.0, 0.0, 0.0, 1.0 },
+ { -1.0, 1.0, 0.0, 1.0, 1.0, 0.0, 0.0, 1.0 },
+ { -0.875, -1.0, 0.0, 1.0, 1.0, 0.0, 0.0, 1.0 },
+ { -0.875, 1.0, 0.0, 1.0, 1.0, 0.0, 0.0, 1.0 },
+ { -1.0, 1.0, 0.0, 1.0, 1.0, 0.0, 0.0, 1.0 }
+ };
+
+ /* Setup program and initial buffer contents */
+ glBindBuffer(GL_ARRAY_BUFFER, bufs[0]);
+ glBufferData(GL_ARRAY_BUFFER,
+ sizeof(initial_vertex_data), initial_vertex_data,
+ GL_STREAM_COPY);
+ glBindBuffer(GL_TRANSFORM_FEEDBACK_BUFFER, bufs[1]);
+ glBufferData(GL_TRANSFORM_FEEDBACK_BUFFER,
+ sizeof(initial_dummy_data), initial_dummy_data,
+ GL_STREAM_COPY);
+ glEnableVertexAttribArray(0);
+ glEnableVertexAttribArray(1);
+
+ piglit_UseProgram(prog);
+ glClear(GL_COLOR_BUFFER_BIT);
+
+ /* Draw 16 times, swapping transform feedback and vertex data
+ * so that transform feedback output is fed back to vertex
+ * input.
+ */
+ for (i = 0; i < 16; ++i) {
+ glBindBuffer(GL_ARRAY_BUFFER, bufs[i % 2]);
+ piglit_BindBufferBase(GL_TRANSFORM_FEEDBACK_BUFFER, 0,
+ bufs[(i + 1) % 2]);
+ glVertexAttribPointer(0, 4, GL_FLOAT, GL_FALSE,
+ 8 * sizeof(float), (void *) 0);
+ glVertexAttribPointer(1, 4, GL_FLOAT, GL_FALSE,
+ 8 * sizeof(float),
+ (void *) (4 * sizeof(float)));
+ piglit_BeginTransformFeedback(GL_TRIANGLES);
+ glDrawArrays(GL_TRIANGLES, 0, 6);
+ piglit_EndTransformFeedback();
+ }
+
+ /* Check that the proper gradient was drawn */
+ for (i = 0; i < 16; ++i) {
+ float expected_color[3] = {i/16.0, (16 - i)/16.0, i/16.0 };
+ pass = piglit_probe_rect_rgb(16 * i, 0, 16, 16,
+ expected_color) && pass;
+ }
+
+ piglit_present_results();
+
+ return pass ? PIGLIT_PASS : PIGLIT_FAIL;
+}
--
1.7.6.4
More information about the Piglit
mailing list