[Piglit] [PATCH] gl-1.5-vertex-buffer-offsets: test unusual vertex offsets/strides

[Brian Paul]

The draw-vertices tests exercises unusual vertex sizes and strides,
but not with interleaved arrays.

This test creates a VBO with interleaved vertex positions and colors.
The colors are positioned at offsets like 9, 10 and 11 bytes from the
start of the vertex.  Unusual strides between vertices are tested too.

Exercises a bug in Gallium's u_vbuf code where the driver was passed
pipe_vertex_element::src_offset values which weren't a multiple of
four, even when PIPE_CAP_VERTEX_ELEMENT_SRC_OFFSET_4BYTE_ALIGNED_ONLY
returned 1.
---
 tests/all.py                              |   1 +
 tests/spec/gl-1.5/CMakeLists.gl.txt       |   1 +
 tests/spec/gl-1.5/vertex-buffer-offsets.c | 124 ++++++++++++++++++++++++++++++
 3 files changed, 126 insertions(+)
 create mode 100644 tests/spec/gl-1.5/vertex-buffer-offsets.c

diff --git a/tests/all.py b/tests/all.py
index ad4c494..ee11be6 100755
--- a/tests/all.py
+++ b/tests/all.py
@@ -1042,6 +1042,7 @@ with profile.group_manager(
       'normal3b3s-invariance-byte', run_concurrent=False)
     g(['gl-1.5-normal3b3s-invariance', 'GL_SHORT'],
       'normal3b3s-invariance-short', run_concurrent=False)
+    g(['gl-1.5-vertex-buffer-offsets'], 'vertex-buffer-offsets')
 
 with profile.group_manager(
         PiglitGLTest,
diff --git a/tests/spec/gl-1.5/CMakeLists.gl.txt b/tests/spec/gl-1.5/CMakeLists.gl.txt
index 8dcd95d..f10c6cb 100644
--- a/tests/spec/gl-1.5/CMakeLists.gl.txt
+++ b/tests/spec/gl-1.5/CMakeLists.gl.txt
@@ -10,5 +10,6 @@ link_libraries (
 )
 
 piglit_add_executable (gl-1.5-normal3b3s-invariance normal3b3s-invariance.c)
+piglit_add_executable (gl-1.5-vertex-buffer-offsets vertex-buffer-offsets.c)
 
 # vim: ft=cmake:
diff --git a/tests/spec/gl-1.5/vertex-buffer-offsets.c b/tests/spec/gl-1.5/vertex-buffer-offsets.c
new file mode 100644
index 0000000..6d58331
--- /dev/null
+++ b/tests/spec/gl-1.5/vertex-buffer-offsets.c
@@ -0,0 +1,124 @@
+/*
+ * Copyright 2015  VMware, Inc.
+ *
+ * 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.
+ */
+
+/*
+ * Test interleaved vertex arrays with unusual element offsets and strides.
+ * Brian Paul
+ */
+
+#include "piglit-util-gl.h"
+
+PIGLIT_GL_TEST_CONFIG_BEGIN
+	config.supports_gl_compat_version = 15;
+	config.window_visual = PIGLIT_GL_VISUAL_RGBA | PIGLIT_GL_VISUAL_DOUBLE;
+PIGLIT_GL_TEST_CONFIG_END
+
+
+void
+piglit_init(int argc, char **argv)
+{
+	/* nothing */
+}
+
+
+static bool
+test_offset_stride(int color_offset, int stride)
+{
+	static const GLfloat vertex[4][2] = {
+		{ -1, -1 },
+		{  1, -1 },
+		{  1,  1 },
+		{ -1,  1 }
+	};
+	static const GLfloat color[4] = { 0.0, 1.0, 0.5, 1.0 };
+	GLubyte buffer[1000];
+	GLuint buf;
+	int i, pos;
+	bool p;
+
+	assert(color_offset >= sizeof(vertex[0]));
+	assert(stride >= color_offset + sizeof(color));
+
+	pos = 0;
+	for (i = 0; i < 4; i++) {
+		/* copy vertex position into buffer */
+		memcpy(buffer + pos, vertex[i], sizeof(vertex[i]));
+
+		/* copy vertex color into buffer at unusual offset */
+		memcpy(buffer + pos + color_offset, color, sizeof(color));
+
+		pos += stride;
+	}
+	assert(pos <= sizeof(buffer));
+
+	glGenBuffers(1, &buf);
+	glBindBuffer(GL_ARRAY_BUFFER, buf);
+	glBufferData(GL_ARRAY_BUFFER, sizeof(buffer),
+					 buffer, GL_STATIC_DRAW);
+
+	glVertexPointer(2, GL_FLOAT, stride, (void *) 0);
+	glColorPointer(4, GL_FLOAT, stride, (void *) (size_t) color_offset);
+	glEnable(GL_VERTEX_ARRAY);
+	glEnable(GL_COLOR_ARRAY);
+
+	glClear(GL_COLOR_BUFFER_BIT);
+	glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
+
+	p = piglit_probe_rect_rgba(0, 0, piglit_width, piglit_height, color);
+
+	if (!p) {
+		printf("failure for color_offset %d, stride %d\n",
+		       color_offset, stride);
+	}
+
+	piglit_present_results();
+
+	glDeleteBuffers(1, &buf);
+
+	return p;
+}
+
+
+enum piglit_result
+piglit_display(void)
+{
+	bool pass = true;
+
+	/* test nice values */
+	pass = test_offset_stride(8, 24) && pass;
+	pass = test_offset_stride(12, 28) && pass;
+
+	/* test unual offset */
+	pass = test_offset_stride(9, 32) && pass;
+
+	/* test unual stride */
+	pass = test_offset_stride(8, 27) && pass;
+
+	/* test unusual offset, unusual stride */
+	pass = test_offset_stride(9, 25) && pass;
+	pass = test_offset_stride(10, 26) && pass;
+	pass = test_offset_stride(11, 27) && pass;
+
+	return pass ? PIGLIT_PASS : PIGLIT_FAIL;
+}
+
-- 
1.9.1