[Piglit] [PATCH v2] primitive-restart: extend the test to catch regressions of bug-109451

[asimiklit.work at gmail.com]

From: Andrii Simiklit <andrii.simiklit at globallogic.com>

Looks like this test should be able to catch this kind of the regressions
os I add it here.
This test should draw green rectangle if everything is ok.
But in case of bug which makes us unable to disable
the primitive restart option it should draw just one triangle.

The solution was suggested.

v2: Added the link to the bug in the comment of the new function
    ( Lionel Landwerlin <lionel.g.landwerlin at intel.com> )

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=109451
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin at intel.com>
Signed-off-by: Andrii Simiklit <andrii.simiklit at globallogic.com>
---
 tests/general/primitive-restart.c | 73 +++++++++++++++++++++++++++++++
 1 file changed, 73 insertions(+)

diff --git a/tests/general/primitive-restart.c b/tests/general/primitive-restart.c
index 4219a6c5b..941540451 100644
--- a/tests/general/primitive-restart.c
+++ b/tests/general/primitive-restart.c
@@ -75,6 +75,11 @@ static bool Have_31;
 static bool TestGL31;
 
 
+static void
+enable_restart(GLuint restart_index);
+static void
+disable_restart(void);
+
 static bool
 check_rendering(void)
 {
@@ -184,6 +189,72 @@ test_begin_end(GLenum primMode)
    return pass;
 }
 
+static void
+write_vec2_value(GLfloat * verts, GLuint vidx, GLfloat x, GLfloat y)
+{
+   verts[(vidx * 2) + 0] = x;
+   verts[(vidx * 2) + 1] = y;
+}
+/* This test should draw green rectangle if everything is ok.
+ * But in case of bug which makes us unable to disable
+ * the primitive restart option it should draw just one triangle.
+ * Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=109451
+ */
+static bool
+test_shared_ib_restart()
+{
+   bool pass = true;
+   GLfloat verts[256 * 2];
+   memset(&verts, 0, sizeof(verts));
+   //left-bottom
+   write_vec2_value(verts, 0, 0.0f, 0.0f);
+   //right-bottom
+   write_vec2_value(verts, 1, piglit_width, 0.0f);
+   //left-top
+   write_vec2_value(verts, 2, 0.0f, piglit_height);
+   //right-top
+   write_vec2_value(verts, 255, piglit_width, piglit_height);
+
+   const GLubyte indices[] = { 0, 1, 2, 255, 0 };
+   const GLfloat expected[3] = { 0.0f, 1.0f, 0.0f };
+   GLuint vbo1, vbo2;
+
+   piglit_ortho_projection(piglit_width, piglit_height, GL_FALSE);
+
+   glClear(GL_COLOR_BUFFER_BIT);
+
+   glColor4fv(green);
+
+   glGenBuffers(1, &vbo1);
+   glBindBuffer(GL_ARRAY_BUFFER, vbo1);
+   glBufferData(GL_ARRAY_BUFFER, sizeof(verts), verts, GL_DYNAMIC_DRAW);
+   glVertexPointer(2, GL_FLOAT, 0, (void *)0);
+
+   glGenBuffers(1, &vbo2);
+   glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, vbo2);
+   glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices, GL_STATIC_DRAW);
+   glEnableClientState(GL_VERTEX_ARRAY);
+
+   //We should draw something with an enabled restart option to check that
+   //it could be correctly disabled
+   enable_restart(0xff);
+   glDrawElements(GL_LINE_STRIP, ARRAY_SIZE(indices), GL_UNSIGNED_BYTE, (void*)0);
+   disable_restart();
+
+   //Draw full screen rectangle
+   glDrawElements(GL_TRIANGLE_STRIP, ARRAY_SIZE(indices) - 1, GL_UNSIGNED_BYTE, (void*)0);
+
+   glDisableClientState(GL_VERTEX_ARRAY);
+   glBindBuffer(GL_ARRAY_BUFFER, 0);
+   glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
+   glDeleteBuffers(1, &vbo1);
+   glDeleteBuffers(1, &vbo2);
+   glFinish();
+   pass = (piglit_probe_rect_rgb(0, 0, piglit_width, piglit_height, expected) != 0) && pass;
+   piglit_present_results();
+   return pass;
+}
+
 
 static void
 enable_restart(GLuint restart_index)
@@ -503,6 +574,7 @@ primitive_restart_test(VBO_CFG vbo_cfg)
 
    if (Have_NV) {
       TestGL31 = false;
+      pass = test_shared_ib_restart() && pass;
       pass = test_begin_end(GL_TRIANGLE_STRIP) && pass;
       pass = test_begin_end(GL_LINE_STRIP) && pass;
       pass = test_draw_elements(vbo_cfg, GL_TRIANGLE_STRIP, GL_UNSIGNED_BYTE) && pass;
@@ -521,6 +593,7 @@ primitive_restart_test(VBO_CFG vbo_cfg)
 
    if (Have_31) {
       TestGL31 = true;
+      pass = test_shared_ib_restart() && pass;
       pass = test_draw_elements(vbo_cfg, GL_TRIANGLE_STRIP, GL_UNSIGNED_BYTE) && pass;
       pass = test_draw_elements(vbo_cfg, GL_TRIANGLE_STRIP, GL_UNSIGNED_SHORT) && pass;
       pass = test_draw_elements(vbo_cfg, GL_TRIANGLE_STRIP, GL_UNSIGNED_INT) && pass;
-- 
2.17.1