AMD_vertex_shader_layer: Add depth render test

This tests layered depth rendering in the vertex shader.

Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>

2 files changed, 239 insertions, 0 deletions

diff --git a/tests/spec/amd_vertex_shader_layer/CMakeLists.gl.txt b/tests/spec/amd_vertex_shader_layer/CMakeLists.gl.txt
index f069be14d..6f64d9432 100644
--- a/tests/spec/amd_vertex_shader_layer/CMakeLists.gl.txt
+++ b/tests/spec/amd_vertex_shader_layer/CMakeLists.gl.txt
@@ -10,3 +10,4 @@ link_libraries (
 )
 
 piglit_add_executable (amd_vertex_shader_layer-layered-2d-texture-render layered-2d-texture-render.c)
+piglit_add_executable (amd_vertex_shader_layer-layered-depth-texture-render layered-depth-texture-render.c)
diff --git a/tests/spec/amd_vertex_shader_layer/layered-depth-texture-render.c b/tests/spec/amd_vertex_shader_layer/layered-depth-texture-render.c
new file mode 100644
index 000000000..8e13d6add
--- /dev/null
+++ b/tests/spec/amd_vertex_shader_layer/layered-depth-texture-render.c
@@ -0,0 +1,238 @@
+/*
+ * Copyright (c) 2013 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.
+ *
+ */
+
+/*
+ * Test 2D depth array texture rendering with gl_Layer (AMD_vertex_shader_layer)
+ *
+ * This test uses layered rendering (gl_Layer) within the vertex shader.
+ * Support for gl_Layer in VS is added by the AMD_vertex_shader_layer
+ * extension.
+ *
+ * This test first renders to a depth array texture which is attached to
+ * a framebuffer. The texture has 5 layers and 7 LODs.
+ *
+ * Once depths have been rendered to each array slice & LOD, the test
+ * then verifies the depth value in each array slice & LOD.
+ */
+
+#include "piglit-util-gl-common.h"
+
+#define PAD		5
+#define SIZE		64
+#define LAYERS		5
+#define LOD		7
+#define DRAW_COUNT	LAYERS * LOD
+#define STRINGIFY(x)    #x
+#define EXP_STRINGIFY(x) STRINGIFY(x)
+
+PIGLIT_GL_TEST_CONFIG_BEGIN
+
+	config.supports_gl_core_version = 31;
+	config.supports_gl_compat_version = 31;
+
+	config.window_width = (((SIZE+PAD)*LAYERS)+PAD);
+	config.window_height = (((SIZE+PAD)*2)+PAD);
+	config.window_visual = PIGLIT_GL_VISUAL_DOUBLE | PIGLIT_GL_VISUAL_RGB;
+
+PIGLIT_GL_TEST_CONFIG_END
+
+static GLuint rectangle_vertices_bo;
+
+/* VS and FS to fill the 2D array texture */
+static const char *fill_tex_vs = 
+ "#version 140\n"
+ "#extension GL_AMD_vertex_shader_layer: enable\n"
+ "uniform int drawing_level;\n"
+ "in vec2 vertex;\n"
+ "out vec3 color;\n"
+ "int num_layers = " EXP_STRINGIFY(LAYERS) ";\n"
+ "int draw_count = " EXP_STRINGIFY(DRAW_COUNT) ";\n"
+ "float get_z()\n"
+ "{\n"
+ " return float((drawing_level * num_layers) + gl_InstanceID) / draw_count;\n"
+  "}\n"
+ "void main()\n"
+ "{\n"
+ " gl_Position = vec4(vertex, get_z(), 1.0);\n"
+ " gl_Layer = gl_InstanceID;\n"
+ "}\n";
+
+static GLuint fill_tex_program;
+
+static bool
+render_tex_layers(GLuint tex)
+{
+	int lod;
+	GLint drawing_level_loc, vertex_loc;
+	GLenum status;
+	int color_index = 0;
+	int size;
+
+	glUseProgram(fill_tex_program);
+
+	drawing_level_loc = glGetUniformLocation(fill_tex_program, "drawing_level");
+
+	glBindBuffer(GL_ARRAY_BUFFER, rectangle_vertices_bo);
+	vertex_loc = glGetAttribLocation(fill_tex_program, "vertex");
+	glVertexAttribPointer(vertex_loc, 2, GL_FLOAT, 0, 0, 0);
+	glEnableVertexAttribArray(vertex_loc);
+	for (lod = 0; lod < LOD; lod++) {
+		size = SIZE >> lod;
+		glFramebufferTexture(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, tex, lod);
+		status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
+		if (status != GL_FRAMEBUFFER_COMPLETE) {
+			fprintf(stderr, "fbo incomplete (status = %s)\n",
+			        piglit_get_gl_enum_name(status));
+			return false;
+		}
+
+		/* Clear background to gray */
+		glClearDepth(1.0);
+		glClear(GL_DEPTH_BUFFER_BIT);
+
+		glViewport(0, 0, size, size);
+		glUniform1i(drawing_level_loc, lod);
+		glDrawArraysInstanced(GL_TRIANGLE_STRIP, 0, 4, LAYERS);
+		color_index += LAYERS;
+	}
+	glFramebufferTexture(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, 0, 0);
+	glDisableVertexAttribArray(vertex_loc);
+
+	return true;
+}
+
+static GLuint
+build_texture(void)
+{
+	GLuint tex;
+	int lod;
+	int size;
+
+	glGenTextures(1, &tex);
+	glBindTexture(GL_TEXTURE_2D_ARRAY, tex);
+	for (lod = 0; lod < LOD; lod++) {
+		size = SIZE >> lod;
+		glTexImage3D(GL_TEXTURE_2D_ARRAY, lod, GL_DEPTH_COMPONENT,
+		             size, size, LAYERS, 0, GL_DEPTH_COMPONENT, GL_FLOAT, NULL);
+	}
+
+	render_tex_layers(tex);
+
+	return tex;
+}
+
+/* Attach the texture layer/lod to the read framebuffer
+ */
+static void
+set_up_read_framebuffer(GLuint tex, int level, int layer)
+{
+	GLenum status;
+
+	glFramebufferTextureLayer(GL_READ_FRAMEBUFFER,
+				  GL_DEPTH_ATTACHMENT,
+				  tex, level, layer);
+
+	status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
+	if (status == GL_FRAMEBUFFER_UNSUPPORTED && level == 0) {
+		printf("This buffer combination is unsupported\n");
+		piglit_report_result(PIGLIT_SKIP);
+	} else if (status != GL_FRAMEBUFFER_COMPLETE) {
+		printf("FBO incomplete at miplevel %d\n", level);
+		piglit_report_result(PIGLIT_FAIL);
+	}
+}
+
+static GLboolean
+test_texture(GLuint tex)
+{
+	int layer, lod;
+	GLboolean retval = GL_TRUE;
+	float expected;
+	float draw_count = LAYERS * LOD;
+	int dim = SIZE;
+
+	for (lod = 0; lod < LOD; lod++) {
+		for (layer = 0; layer < LAYERS; layer++) {
+			GLboolean pass;
+			set_up_read_framebuffer(tex, lod, layer);
+			expected = ((float)(lod * LAYERS) + layer) / draw_count;
+			expected = (expected / 2.0) + 0.5;
+			pass = piglit_probe_rect_depth(0, 0, dim, dim, expected);
+			retval = retval && pass;
+		}
+		dim >>= 1;
+	}
+
+	return retval;
+}
+
+enum piglit_result
+piglit_display(void)
+{
+	GLboolean pass;
+	GLuint vao, fbo;
+	GLuint tex;
+	static const GLfloat verts[4][2] = {
+		{ 1.0, -1.0},
+		{-1.0, -1.0},
+		{ 1.0,  1.0},
+		{-1.0,  1.0},
+	};
+
+	glEnable(GL_DEPTH_TEST);
+
+	glGenFramebuffers(1, &fbo);
+	glBindFramebuffer(GL_FRAMEBUFFER, fbo);
+	glGenVertexArrays(1, &vao);
+	glBindVertexArray(vao);
+	glGenBuffers(1, &rectangle_vertices_bo);
+	glBindBuffer(GL_ARRAY_BUFFER, rectangle_vertices_bo);
+	glBufferData(GL_ARRAY_BUFFER, sizeof(verts), verts, GL_STATIC_DRAW);
+
+	tex = build_texture();
+	pass = test_texture(tex);
+	glDeleteTextures(1, &tex);
+
+	glDeleteBuffers(1, &rectangle_vertices_bo);
+	glDeleteFramebuffers(1, &fbo);
+	glDeleteVertexArrays(1, &vao);
+
+	return pass ? PIGLIT_PASS : PIGLIT_FAIL;
+}
+
+void
+piglit_init(int argc, char **argv)
+{
+	/* For glFramebufferTexture we need either GL 3.2 or
+	 * GL_ARB_geometry_shader4.
+	 */
+	if (piglit_get_gl_version() < 32) {
+		piglit_require_extension("GL_ARB_geometry_shader4");
+	}
+
+	piglit_require_extension("GL_AMD_vertex_shader_layer");
+
+	fill_tex_program = piglit_build_simple_program(fill_tex_vs, NULL);
+	piglit_check_gl_error(GL_NO_ERROR);
+}