glsl-fs-discard-02: Test that early depth writes don't happen with "discard".

5 files changed, 156 insertions, 0 deletions

diff --git a/tests/all.tests b/tests/all.tests
index e5aa0688..bab2262f 100644
--- a/tests/all.tests
+++ b/tests/all.tests
@@ -275,6 +275,7 @@ add_shader_generic(shaders, 'glsl-fs-cross')
 add_shader_generic(shaders, 'glsl-fs-cross-2')
 add_shader_generic(shaders, 'glsl-fs-cross-3')
 add_shader_generic(shaders, 'glsl-fs-discard-01')
+add_shader_generic(shaders, 'glsl-fs-discard-02')
 add_shader_generic(shaders, 'glsl-fs-dot-vec2')
 add_shader_generic(shaders, 'glsl-fs-exp')
 add_plain_test(shaders, 'glsl-fs-exp2')
diff --git a/tests/shaders/CMakeLists.txt b/tests/shaders/CMakeLists.txt
index 6452bc79..5d25ead6 100644
--- a/tests/shaders/CMakeLists.txt
+++ b/tests/shaders/CMakeLists.txt
@@ -108,6 +108,7 @@ add_executable (vpfp-generic vpfp-generic.cpp)
 add_executable (vp-max-array vp-max-array.c)
 add_executable (glsl-derivs glsl-derivs.c)
 add_executable (glsl-deriv-varyings glsl-deriv-varyings.c)
+add_executable (glsl-fs-discard-02 glsl-fs-discard-02.c)
 add_executable (glsl-fwidth glsl-fwidth.c)
 add_executable (glsl-lod-bias glsl-lod-bias.c)
 add_executable (glsl-preprocessor-comments glsl-preprocessor-comments.c)
diff --git a/tests/shaders/glsl-fs-discard-02.c b/tests/shaders/glsl-fs-discard-02.c
new file mode 100644
index 00000000..0ef6282e
--- /dev/null
+++ b/tests/shaders/glsl-fs-discard-02.c
@@ -0,0 +1,120 @@
+/*
+ * Copyright © 2009 Marek Olšák (maraeo@gmail.com)
+ * Copyright © 2010 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.
+ *
+ * Authors:
+ *    Marek Olšák <mareao@gmail.com>
+ *    Eric Anholt <eric@anholt.net>
+ *
+ */
+
+/** @file glsl-fs-discard-02.c
+ *
+ * Tests that discarding fragments doesn't let early depth writes through.
+ */
+
+#include "piglit-util.h"
+
+int piglit_width = 100, piglit_height = 100;
+int piglit_window_mode = GLUT_RGB | GLUT_ALPHA | GLUT_DOUBLE | GLUT_DEPTH;
+
+static char vs_code[] =
+	"varying vec4 color;"
+	"\n"
+	"void main()\n"
+	"{\n"
+	"	gl_Position = gl_Vertex;\n"
+	"	if (gl_Vertex.z > 0.75)\n"
+	"		color = vec4(1.0, 0.0, 0.0, gl_Vertex.z);\n"
+	"	else if (gl_Vertex.z > 0.25)\n"
+	"		color = vec4(0.0, 1.0, 0.0, gl_Vertex.z);\n"
+	"	else\n"
+	"		color = vec4(0.0, 0.0, 1.0, gl_Vertex.z);\n"
+	"}\n";
+
+static char fs_code[] =
+	"varying vec4 color;\n"
+	"\n"
+	"void main()\n"
+	"{\n"
+	"	if (color.w < 0.25)\n"
+	"		discard;"
+	"    gl_FragColor = vec4(color.xyz, 0.0);\n"
+	"}\n";
+
+static GLuint setup_shaders()
+{
+	GLuint vs, fs, prog;
+
+	vs = piglit_compile_shader_text(GL_VERTEX_SHADER, vs_code);
+	fs = piglit_compile_shader_text(GL_FRAGMENT_SHADER, fs_code);
+	prog = piglit_link_simple_program(vs, fs);
+
+	glUseProgram(prog);
+	return prog;
+}
+
+static GLboolean test()
+{
+	GLint prog, location;
+	GLboolean pass = GL_TRUE;
+	int i;
+	float red[4] =   {1, 0, 0, 0};
+	float green[4] = {0, 1, 0, 0};
+
+	prog = setup_shaders();
+
+	glClear(GL_DEPTH_BUFFER_BIT);
+
+	glDepthFunc(GL_LEQUAL);
+	glEnable(GL_DEPTH_TEST);
+
+	piglit_draw_rect_z(1.0, -1, -1, 2, 2); // red
+	piglit_draw_rect_z(0.0, -1, -1, 2, 2); // discard
+	piglit_draw_rect_z(0.5, -1, -1, 2, 2); // green
+
+	assert(glGetError() == 0);
+
+	piglit_probe_rect_rgba(0, 0, piglit_width, piglit_height, green);
+
+	return pass;
+}
+
+enum piglit_result piglit_display(void)
+{
+	GLboolean pass;
+
+	pass = test();
+
+	glutSwapBuffers();
+
+	return pass ? PIGLIT_SUCCESS : PIGLIT_FAILURE;
+}
+
+void piglit_init(int argc, char **argv)
+{
+	if (!GLEW_VERSION_2_0) {
+		printf("Requires OpenGL 2.0\n");
+		piglit_report_result(PIGLIT_SKIP);
+	}
+}
+
diff --git a/tests/util/piglit-util.c b/tests/util/piglit-util.c
index 962d76bb..ec0488ab 100644
--- a/tests/util/piglit-util.c
+++ b/tests/util/piglit-util.c
@@ -630,6 +630,39 @@ piglit_draw_rect(float x, float y, float w, float h)
 }
 
 /**
+ * Convenience function to draw an axis-aligned rectangle.
+ */
+GLvoid
+piglit_draw_rect_z(float z, float x, float y, float w, float h)
+{
+	float verts[4][4];
+
+	verts[0][0] = x;
+	verts[0][1] = y;
+	verts[0][2] = z;
+	verts[0][3] = 1.0;
+	verts[1][0] = x + w;
+	verts[1][1] = y;
+	verts[1][2] = z;
+	verts[1][3] = 1.0;
+	verts[2][0] = x + w;
+	verts[2][1] = y + h;
+	verts[2][2] = z;
+	verts[2][3] = 1.0;
+	verts[3][0] = x;
+	verts[3][1] = y + h;
+	verts[3][2] = z;
+	verts[3][3] = 1.0;
+
+	glVertexPointer(4, GL_FLOAT, 0, verts);
+	glEnableClientState(GL_VERTEX_ARRAY);
+
+	glDrawArrays(GL_QUADS, 0, 4);
+
+	glDisableClientState(GL_VERTEX_ARRAY);
+}
+
+/**
  * Convenience function to draw an axis-aligned rectangle
  * with texture coordinates.
  */
diff --git a/tests/util/piglit-util.h b/tests/util/piglit-util.h
index ebaf5bd4..1873a6e9 100644
--- a/tests/util/piglit-util.h
+++ b/tests/util/piglit-util.h
@@ -100,6 +100,7 @@ GLuint piglit_compile_shader_text(GLenum target, const char *text);
 GLboolean piglit_link_check_status(GLint prog);
 GLint piglit_link_simple_program(GLint vs, GLint fs);
 GLvoid piglit_draw_rect(float x, float y, float w, float h);
+GLvoid piglit_draw_rect_z(float z, float x, float y, float w, float h);
 GLvoid piglit_draw_rect_tex(float x, float y, float w, float h,
                             float tx, float ty, float tw, float th);
 void piglit_escape_exit_key(unsigned char key, int x, int y);