Verifies the screen position specified by glViewport is not effected by
the GL_CLIP_ORIGIN state.
Passes with nvidia, fails with Mesa until _mesa_get_viewport_xform()
is fixed.
v2: also enable back-face culling to make sure front/back-face polygon
orientation isn't upset by the clip origin.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93813
---
tests/all.py | 1 +
tests/spec/arb_clip_control/CMakeLists.gl.txt | 1 +
tests/spec/arb_clip_control/viewport.c | 202
++++++++++++++++++++++++++
3 files changed, 204 insertions(+)
create mode 100644 tests/spec/arb_clip_control/viewport.c
diff --git a/tests/all.py b/tests/all.py
index b494ed6..4e6bb1d 100644
--- a/tests/all.py
+++ b/tests/all.py
@@ -2552,6 +2552,7 @@ with profile.group_manager(
PiglitGLTest, grouptools.join('spec', 'arb_clip_control'))
as g:
g(['arb_clip_control-clip-control'])
g(['arb_clip_control-depth-precision'])
+ g(['arb_clip_control-viewport'])
with profile.group_manager(
PiglitGLTest, grouptools.join('spec',
'arb_color_buffer_float')) as g:
diff --git a/tests/spec/arb_clip_control/CMakeLists.gl.txt
b/tests/spec/arb_clip_control/CMakeLists.gl.txt
index 7038366..3f55663 100644
--- a/tests/spec/arb_clip_control/CMakeLists.gl.txt
+++ b/tests/spec/arb_clip_control/CMakeLists.gl.txt
@@ -10,5 +10,6 @@ link_libraries (
piglit_add_executable (arb_clip_control-clip-control clip-control.c)
piglit_add_executable (arb_clip_control-depth-precision
clip-control-depth-precision.c)
+piglit_add_executable (arb_clip_control-viewport viewport.c)
# vim: ft=cmake:
diff --git a/tests/spec/arb_clip_control/viewport.c
b/tests/spec/arb_clip_control/viewport.c
new file mode 100644
index 0000000..9d41ae9
--- /dev/null
+++ b/tests/spec/arb_clip_control/viewport.c
@@ -0,0 +1,202 @@
+/*
+ * Copyright (C) 2016 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 glViewport behaviour with GL_ARB_clip_control.
+ * The position of the viewport in window coordinates should not be
+ * effected by the GL_CLIP_ORIGIN state.
+ *
+ * See https://bugs.freedesktop.org/show_bug.cgi?id=93813
+ *
+ * Brian Paul
+ * 9 Feb 2016
+ */
+
+#include "piglit-util-gl.h"
+
+
+PIGLIT_GL_TEST_CONFIG_BEGIN
+ config.supports_gl_compat_version = 20;
+ config.window_visual = PIGLIT_GL_VISUAL_DOUBLE |
PIGLIT_GL_VISUAL_RGBA;
+PIGLIT_GL_TEST_CONFIG_END
+
+
+static const float red[3] = { 1, 0, 0 };
+static const float green[3] = { 0, 1, 0 };
+static const float blue[3] = { 0, 0, 1 };
+static const float white[3] = { 1, 1, 1 };
+
+
+void
+piglit_init(int argc, char **argv)
+{
+ piglit_require_extension("GL_ARB_clip_control");
+ glEnable(GL_CULL_FACE);
+}
+
+
+/**
+ * Draw this pattern in the current viewport region, regardless of
+ * the clip control settings:
+ *
+ * +---------+---------+
+ * | | |
+ * | blue | white |
+ * | | |
+ * +---------+---------+
+ * | | |
+ * | red | green |
+ * | | |
+ * +---------+---------+
+ *
+ * \param invert_y - if true, NDC_Y=-1=top, else NDC_Y=-1=bottom
+ */
+static void
+draw_test_pattern(bool invert_y)
+{
+ /* Since the modelview and projection matrices are identity
matrices,
+ * we're effectively drawing in Normalized Device Coordinates which
+ * range from [-1,1] in X and Y.
+ *
+ * Note: we're careful with our glRectf coordinates so that the
+ * rect is drawn front-facing. If a rect is not drawn it must be
+ * because it was back-face culled by mistake.
+ */
+
+ /* lower-left quadrant = red */
+ glColor3fv(red);
+ if (invert_y)
+ glRectf(-1, 0, 0, 1);
+ else
+ glRectf(-1, -1, 0, 0);
+
+ /* lower-right quadrant = green */
+ glColor3fv(green);
+ if (invert_y)
+ glRectf(0, 0, 1, 1);
+ else
+ glRectf(0, -1, 1, 0);
+
+ /* upper-left quadrant = blue */
+ glColor3fv(blue);
+ if (invert_y)
+ glRectf(-1, -1, 0, 0);
+ else
+ glRectf(-1, 0, 0, 1);
+
+ /* upper-right quadrant = white */
+ glColor3fv(white);
+ if (invert_y)
+ glRectf(0, -1, 1, 0);
+ else
+ glRectf(0, 0, 1, 1);
+}
+
+
+static bool
+check_test_pattern(int xpos, int ypos)
+{
+ bool pass = true;
+ int half_w = piglit_width / 2;
+ int half_h = piglit_height / 2;
+ /* coords in center of the color swatches */
+ int x0 = xpos + half_w / 4;
+ int y0 = ypos + half_h / 4;
+ int x1 = xpos + half_w * 3 / 4;
+ int y1 = ypos + half_h * 3 / 4;
+
+ if (!piglit_probe_pixel_rgb(x0, y0, red)) {
+ printf("wrong color in lower-left quadrant of test pattern\n");
+ pass = false;
+ }
+
+ if (!piglit_probe_pixel_rgb(x1, y0, green)) {
+ printf("wrong color in lower-right quadrant of test pattern\n");
+ pass = false;
+ }
+
+ if (!piglit_probe_pixel_rgb(x0, y1, blue)) {
+ printf("wrong color in upper-left quadrant of test pattern\n");
+ pass = false;
+ }
+
+ if (!piglit_probe_pixel_rgb(x1, y1, white)) {
+ printf("wrong color in upper-right quadrant of test pattern\n");
+ pass = false;
+ }
+
+ if (!pass) {
+ GLint origin;
+ glGetIntegerv(GL_CLIP_ORIGIN, &origin);
+ printf("GL_CLIP_ORIGIN = %s\n",
+ piglit_get_gl_enum_name(origin));
+ }
+
+ return pass;
+}
+
+
+enum piglit_result
+piglit_display(void)
+{
+ int half_w = piglit_width / 2;
+ int half_h = piglit_height / 2;
+ bool pass = true;
+
+ /* Test normal GL coordinates */
+ glClipControl(GL_LOWER_LEFT, GL_NEGATIVE_ONE_TO_ONE);
+ glClear(GL_COLOR_BUFFER_BIT);
+
+ /* Normal GL origin / Draw in upper-left screen quadrant */
+ glViewport(0, half_h, half_w, half_h);
+ draw_test_pattern(false);
+ if (!check_test_pattern(0, half_h))
+ pass = false;
+
+ /* Normal GL origin / Draw in lower-right screen quadrant */
+ glViewport(half_w, 0, half_w, half_h);
+ draw_test_pattern(false);
+ if (!check_test_pattern(half_w, 0))
+ pass = false;
+
+
+ /* Test inverted GL coordinates */
+ glClipControl(GL_UPPER_LEFT, GL_NEGATIVE_ONE_TO_ONE);
+ glClear(GL_COLOR_BUFFER_BIT);
+
+ /* Inverted GL origin / Draw in upper-left screen quadrant */
+ glViewport(0, half_h, half_w, half_h);
+ draw_test_pattern(true);
+ if (!check_test_pattern(0, half_h))
+ pass = false;
+
+ /* Inverted GL origin / Draw in lower-right screen quadrant */
+ glViewport(half_w, 0, half_w, half_h);
+ draw_test_pattern(true);
+ if (!check_test_pattern(half_w, 0))
+ pass = false;
+
+ piglit_present_results();
+
+ return pass ? PIGLIT_PASS : PIGLIT_FAIL;
+}
