Test GL_ARB_clear_texture using cube map textures

This adds a test for glClearTexSubImage when clearing a sub-region of
a cube map texture. Each face of the cube map is cleared to a separate
colour and then one pixel of each face is rendered using points. The
colours are then probed to check whether the clear worked. This is
important to test because glClearTexSubImage has some unusual
semantics in that the zoffset parameter is used to select the cube
face.

Reviewed-by: Brian Paul <brianp@vmware.com>

2 files changed, 236 insertions, 0 deletions

diff --git a/tests/spec/arb_clear_texture/CMakeLists.gl.txt b/tests/spec/arb_clear_texture/CMakeLists.gl.txt
index 75ac54c0d..697e84f78 100644
--- a/tests/spec/arb_clear_texture/CMakeLists.gl.txt
+++ b/tests/spec/arb_clear_texture/CMakeLists.gl.txt
@@ -10,5 +10,6 @@ link_libraries (
 
 piglit_add_executable (arb_clear_texture-simple simple.c)
 piglit_add_executable (arb_clear_texture-3d 3d.c)
+piglit_add_executable (arb_clear_texture-cube cube.c)
 
 # vim: ft=cmake:
diff --git a/tests/spec/arb_clear_texture/cube.c b/tests/spec/arb_clear_texture/cube.c
new file mode 100644
index 000000000..43df5075e
--- /dev/null
+++ b/tests/spec/arb_clear_texture/cube.c
@@ -0,0 +1,235 @@
+/*
+ * Copyright (c) 2014 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.
+ */
+
+/** @file cube.c
+ *
+ * A test of using glClearTexSubImage to clear faces of a cube
+ * texture. Each face is cleared to a separate color and then all of
+ * the faces are rendered and probed.
+ */
+
+#include "piglit-util-gl-common.h"
+
+struct vertex {
+	float pos;
+	float tex_coord[3];
+};
+
+struct face {
+	/* Color used for this face */
+	float color[3];
+	/* Texture coordinates needed to access this face */
+	float tex_coord[3];
+
+	GLenum target;
+};
+
+static const struct face
+faces[] = {
+	{ { 0.0f, 0.0f, 1.0f }, { +1.0f, 0.0f, 0.0f },
+	  GL_TEXTURE_CUBE_MAP_POSITIVE_X },
+	{ { 0.0f, 1.0f, 0.0f }, { -1.0f, 0.0f, 0.0f },
+	  GL_TEXTURE_CUBE_MAP_NEGATIVE_X },
+	{ { 0.0f, 1.0f, 1.0f }, { 0.0f, +1.0f, 0.0f },
+	  GL_TEXTURE_CUBE_MAP_POSITIVE_Y },
+	{ { 1.0f, 0.0f, 0.0f }, { 0.0f, -1.0f, 0.0f },
+	  GL_TEXTURE_CUBE_MAP_NEGATIVE_Y },
+	{ { 1.0f, 0.0f, 1.0f }, { 0.0f, 0.0f, +1.0f },
+	  GL_TEXTURE_CUBE_MAP_POSITIVE_Z },
+	{ { 1.0f, 1.0f, 0.0f }, { 0.0f, 0.0f, -1.0f },
+	  GL_TEXTURE_CUBE_MAP_NEGATIVE_Z },
+};
+
+PIGLIT_GL_TEST_CONFIG_BEGIN
+
+	config.supports_gl_compat_version = 20;
+	config.supports_gl_es_version = 20;
+
+	config.window_visual = PIGLIT_GL_VISUAL_RGB | PIGLIT_GL_VISUAL_DOUBLE;
+
+PIGLIT_GL_TEST_CONFIG_END
+
+static GLuint
+create_texture(void)
+{
+	GLuint tex;
+	int i;
+
+	glGenTextures(1, &tex);
+	glBindTexture(GL_TEXTURE_CUBE_MAP, tex);
+
+	glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+
+	for (i = 0; i < 6; i++) {
+		glTexImage2D(faces[i].target,
+			     0, /* level */
+			     GL_RGB,
+			     1, 1, /* width/height */
+			     0, /* border */
+			     GL_RGB,
+			     GL_UNSIGNED_BYTE,
+			     NULL);
+	}
+
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+
+	if (!piglit_check_gl_error(GL_NO_ERROR))
+		piglit_report_result(PIGLIT_FAIL);
+
+	return tex;
+}
+
+static void
+clear_texture(GLuint tex)
+{
+	int i;
+
+	for (i = 0; i < 6; i++) {
+		glClearTexSubImage(tex,
+				   0, /* level */
+				   0, 0, i, /* x/y/z */
+				   1, 1, 1, /* width/height/depth */
+				   GL_RGB,
+				   GL_FLOAT,
+				   faces[i].color);
+	}
+
+	if (!piglit_check_gl_error(GL_NO_ERROR))
+		piglit_report_result(PIGLIT_FAIL);
+}
+
+static void
+init_program(void)
+{
+	GLuint prog;
+	GLuint uniform;
+
+	static const char vs_source[] =
+		"attribute float piglit_vertex;\n"
+		"attribute vec3 piglit_texcoord;\n"
+		"uniform vec2 fb_size;\n"
+		"varying vec3 tex_coord;\n"
+		"\n"
+		"void main()\n"
+		"{\n"
+		"        gl_Position = vec4(vec2(piglit_vertex, 0.5) * 2.0 /\n"
+		"                           fb_size - 1.0,\n"
+		"                           0.0, 1.0);\n"
+		"        tex_coord = piglit_texcoord;\n"
+		"}\n";
+	static const char fs_source[] =
+		"uniform samplerCube tex;\n"
+		"varying vec3 tex_coord;\n"
+		"\n"
+		"void main()\n"
+		"{\n"
+		"        gl_FragColor = textureCube(tex, tex_coord);\n"
+		"}\n";
+
+	prog = piglit_build_simple_program(vs_source, fs_source);
+
+	glUseProgram(prog);
+
+	uniform = glGetUniformLocation(prog, "tex");
+	glUniform1i(uniform, 0);
+
+	uniform = glGetUniformLocation(prog, "fb_size");
+	glUniform2f(uniform, piglit_width, piglit_height);
+}
+
+void
+piglit_init(int argc, char **argv)
+{
+	/* glClearTexture is either in the GL_ARB_clear_texture
+	 * extension or in core in GL 4.4
+	 */
+	if (piglit_get_gl_version() < 44 &&
+	    !piglit_is_extension_supported("GL_ARB_clear_texture")) {
+		printf("OpenGL 4.4 or GL_ARB_clear_texture is required.\n");
+		piglit_report_result(PIGLIT_SKIP);
+	}
+
+	init_program();
+}
+
+static void
+draw_faces(void)
+{
+	struct vertex vertices[6];
+	int i;
+
+	for (i = 0; i < 6; i++) {
+		vertices[i].pos = i + 0.5f;
+		memcpy(vertices[i].tex_coord,
+		       faces[i].tex_coord,
+		       sizeof faces[i].tex_coord);
+	}
+
+	glEnableVertexAttribArray(PIGLIT_ATTRIB_POS);
+	glVertexAttribPointer(PIGLIT_ATTRIB_POS,
+			      1, /* size */
+			      GL_FLOAT,
+			      GL_FALSE, /* normalized */
+			      sizeof vertices[0],
+			      &vertices[0].pos);
+	glEnableVertexAttribArray(PIGLIT_ATTRIB_TEX);
+	glVertexAttribPointer(PIGLIT_ATTRIB_TEX,
+			      3, /* size */
+			      GL_FLOAT,
+			      GL_FALSE, /* normalized */
+			      sizeof vertices[0],
+			      vertices[0].tex_coord);
+
+	glDrawArrays(GL_POINTS, 0, 6);
+
+	glDisableVertexAttribArray(PIGLIT_ATTRIB_POS);
+	glDisableVertexAttribArray(PIGLIT_ATTRIB_TEX);
+}
+
+enum piglit_result
+piglit_display(void)
+{
+	bool pass = true;
+	GLuint tex;
+	int i;
+
+	tex = create_texture();
+
+	clear_texture(tex);
+
+	glBindTexture(GL_TEXTURE_CUBE_MAP, tex);
+
+	draw_faces();
+
+	glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
+
+	glDeleteTextures(1, &tex);
+
+	for (i = 0; i < 6; i++)
+		pass &= piglit_probe_pixel_rgb(i, 0, faces[i].color);
+
+	piglit_present_results();
+
+	return pass ? PIGLIT_PASS : PIGLIT_FAIL;
+}