[Piglit] [PATCH 1/3] primitive-restart-draw-mode: draw front and back faces in different colors

[Marek Olšák]

From: Marek Olšák <marek.olsak at amd.com>

so that triangle strip winding reset is visible after primitive restart
---
 tests/general/primitive-restart-draw-mode.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/tests/general/primitive-restart-draw-mode.c b/tests/general/primitive-restart-draw-mode.c
index cca89e385..5a1379748 100644
--- a/tests/general/primitive-restart-draw-mode.c
+++ b/tests/general/primitive-restart-draw-mode.c
@@ -126,34 +126,36 @@ static const struct test_desc
 };
 
 static const struct test_desc *test = NULL;
 
 
 static const char vs_text[] =
 	"#version 110\n"
 	"attribute vec2 vertex;\n"
 	"uniform vec2 offset;\n"
 	"uniform vec2 window_size;\n"
-	"uniform vec4 color;\n"
+	"uniform vec4 color, bcolor;\n"
 	"void main()\n"
 	"{\n"
 	"  gl_Position = vec4((vertex + offset) / window_size * 2.0 - 1.0,\n"
 	"                     0.0, 1.0);\n"
 	"  gl_FrontColor = color;\n"
+	"  gl_BackColor = bcolor;\n"
 	"}\n";
 
 
 static GLuint prog;
 static GLint vertex_attr;
 static GLint window_size_loc;
 static GLint offset_loc;
 static GLint color_loc;
+static GLint bcolor_loc;
 
 
 static void
 print_usage_and_exit(const char *prog_name)
 {
 	int i;
 	printf("Usage: %s <subtest>\n"
 	       "  where <subtest> is one of the following:\n", prog_name);
 	for (i = 0; i < ARRAY_SIZE(tests); i++)
 		printf("    %s\n", tests[i].name);
@@ -188,28 +190,33 @@ piglit_init(int argc, char **argv)
 
 	vs = piglit_compile_shader_text(GL_VERTEX_SHADER, vs_text);
 	prog = piglit_link_simple_program(vs, 0);
 	if (!prog)
 		piglit_report_result(PIGLIT_FAIL);
 	glDeleteShader(vs);
 	vertex_attr = glGetAttribLocation(prog, "vertex");
 	window_size_loc = glGetUniformLocation(prog, "window_size");
 	offset_loc = glGetUniformLocation(prog, "offset");
 	color_loc = glGetUniformLocation(prog, "color");
+	bcolor_loc = glGetUniformLocation(prog, "bcolor");
+
+	glEnable(GL_VERTEX_PROGRAM_TWO_SIDE);
 }
 
 
 static void
 draw_pattern(int restart_pos, bool use_primitive_restart)
 {
-	/* Draw test pattern in blue */
+	/* Draw front faces blue and back faces red. */
 	glUniform4f(color_loc, 0.25, 0.25, 1.0, 1.0);
+	glUniform4f(bcolor_loc, 0.7, 0.2, 0.2, 1.0);
+
 	if (use_primitive_restart) {
 		GLubyte index_buffer[NUM_VERTICES + 1];
 		int i;
 
 		for (i = 0; i < restart_pos; i++) {
 			index_buffer[i] = i;
 		}
 		index_buffer[restart_pos] = 0xff;
 		for (i = restart_pos + 1; i < ARRAY_SIZE(index_buffer); i++) {
 			index_buffer[i] = i - 1;
-- 
2.17.1