[Piglit] [PATCH] max-samplers: use the maximum number of textures in every shader

Brian Paul brianp at vmware.com
Wed May 8 16:16:52 PDT 2013


On 05/08/2013 11:49 AM, Marek Olšák wrote:
> ---
>   tests/all.tests                     |    1 +
>   tests/spec/gl-3.1/CMakeLists.gl.txt |    1 +
>   tests/spec/gl-3.1/max-samplers.c    |  274 +++++++++++++++++++++++++++++++++++
>   3 files changed, 276 insertions(+)
>   create mode 100644 tests/spec/gl-3.1/max-samplers.c
>
> diff --git a/tests/all.tests b/tests/all.tests
> index 262b44c..b5f64f5 100644
> --- a/tests/all.tests
> +++ b/tests/all.tests
> @@ -704,6 +704,7 @@ gl31 = Group()
>   spec['!OpenGL 3.1'] = gl31
>   gl31['genned-names'] = concurrent_test('gl-3.1-genned-names')
>   gl31['minmax'] = concurrent_test('gl-3.1-minmax')
> +gl31['max-samplers'] = concurrent_test('gl-3.1-max-samplers')
>   for subtest in ['generated', 'written', 'flush']:
>           cmdline = 'primitive-restart-xfb {0}'.format(subtest)
>           gl31[cmdline] = concurrent_test('gl-3.1-' + cmdline)
> diff --git a/tests/spec/gl-3.1/CMakeLists.gl.txt b/tests/spec/gl-3.1/CMakeLists.gl.txt
> index 70eb135..0aaa1f0 100644
> --- a/tests/spec/gl-3.1/CMakeLists.gl.txt
> +++ b/tests/spec/gl-3.1/CMakeLists.gl.txt
> @@ -12,5 +12,6 @@ link_libraries (
>   piglit_add_executable (gl-3.1-genned-names genned-names.c)
>   piglit_add_executable (gl-3.1-minmax minmax.c)
>   piglit_add_executable (gl-3.1-primitive-restart-xfb primitive-restart-xfb.c)
> +piglit_add_executable (gl-3.1-max-samplers max-samplers.c)
>
>   # vim: ft=cmake:
> diff --git a/tests/spec/gl-3.1/max-samplers.c b/tests/spec/gl-3.1/max-samplers.c
> new file mode 100644
> index 0000000..9a9c7e3
> --- /dev/null
> +++ b/tests/spec/gl-3.1/max-samplers.c
> @@ -0,0 +1,274 @@
> +/*
> + * 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<maraeo at gmail.com>
> + */
> +
> +/**
> + * Tests that binding the maximum number of textures in both the vertex and
> + * fragment shader works.
> + */
> +
> +#include<string.h>
> +#include "piglit-util-gl-common.h"
> +
> +PIGLIT_GL_TEST_CONFIG_BEGIN
> +
> +	config.supports_gl_core_version = 31;
> +
> +	config.window_width = 128;
> +	config.window_height = 128;
> +	config.window_visual = PIGLIT_GL_VISUAL_RGB | PIGLIT_GL_VISUAL_DOUBLE;
> +
> +PIGLIT_GL_TEST_CONFIG_END
> +
> +static const char *vs_source =
> +	"#define NUM %i \n"
> +	"uniform sampler2D vertex_tex[NUM]; \n"
> +	"uniform int vertex_index;"
> +	"varying vec3 vertex_tex_color; \n"
> +	"void main() \n"
> +	"{ \n"
> +	"	int i; \n"
> +	"	gl_Position = gl_Vertex; \n"
> +	"	vertex_tex_color = vec3(0.0); \n"
> +	"	for (i = 0; i<  NUM; i++) \n"
> +	"		if (i == vertex_index) \n"
> +	"			vertex_tex_color = texture2DLod(vertex_tex[i], vec2(0.5), 0.0).xyz; \n"
> +	"} \n";

Does this loop (and the fs loop below) get unrolled now with Mesa?

I think variable indexing of sampler uniforms is sometimes trouble to 
implement.  I wouldn't be surprised if an OpenGL driver failed this 
test because of that.  I wrote the mesa-demos/src/glsl/samplers.c test 
to exercise this a long time ago.

With a bit of work, the shader code could be generated without the 
loop.  But I'm OK with it as-is until we find a need to change it.


> +
> +static const char *vs_source_no_textures =
> +	"varying vec3 vertex_tex_color; \n"
> +	"void main() \n"
> +	"{ \n"
> +	"	gl_Position = gl_Vertex; \n"
> +	"	vertex_tex_color = vec3(0.0); \n"
> +	"} \n";
> +
> +static const char *fs_source =
> +	"#define NUM %i \n"
> +	"uniform sampler2D fragment_tex[NUM]; \n"
> +	"uniform int fragment_index;"
> +	"varying vec3 vertex_tex_color; \n"
> +	"void main() \n"
> +	"{ \n"
> +	"	int i; \n"
> +	"	vec3 fragment_tex_color = vec3(0.0); \n"
> +	"	for (i = 0; i<  NUM; i++) \n"
> +	"		if (i == fragment_index) \n"
> +	"			fragment_tex_color = texture2D(fragment_tex[i], vec2(0.5), 0.0).xyz; \n"
> +	"	gl_FragColor = vec4(fragment_tex_color + vertex_tex_color, 1.0); \n"
> +	"} \n";
> +
> +GLuint prog;
> +static int max_vs_textures, max_fs_textures;
> +
> +static void
> +get_texture_color(int unit, float out[3])
> +{
> +	out[0] = (unit % 16) / 15.0;
> +	out[1] = (unit / 16) / 15.0;
> +	out[2] = 0;
> +}
> +
> +static void
> +set_uniform(GLuint prog, const char *name, int value)
> +{
> +	GLuint loc = glGetUniformLocation(prog, name);
> +	if (loc != -1)
> +		glUniform1i(loc, value);
> +}
> +
> +static GLvoid
> +draw_rect_core(int ix, int iy, int iw, int ih)
> +{
> +	float x = -1 + 2.0*ix/piglit_width;
> +	float y = -1 + 2.0*iy/piglit_height;
> +	float w = 2.0*iw/piglit_width;
> +	float h = 2.0*ih/piglit_height;
> +	float verts[4][4];
> +	GLuint vbo;
> +
> +	verts[0][0] = x;
> +	verts[0][1] = y;
> +	verts[0][2] = 0.0;
> +	verts[0][3] = 1.0;
> +	verts[1][0] = x + w;
> +	verts[1][1] = y;
> +	verts[1][2] = 0.0;
> +	verts[1][3] = 1.0;
> +	verts[2][0] = x + w;
> +	verts[2][1] = y + h;
> +	verts[2][2] = 0.0;
> +	verts[2][3] = 1.0;
> +	verts[3][0] = x;
> +	verts[3][1] = y + h;
> +	verts[3][2] = 0.0;
> +	verts[3][3] = 1.0;
> +
> +	glGenBuffers(1,&vbo);
> +	glBindBuffer(GL_ARRAY_BUFFER, vbo);
> +	glBufferData(GL_ARRAY_BUFFER, sizeof(verts), verts, GL_STATIC_DRAW);
> +
> +	glEnableVertexAttribArray(0);
> +	glVertexAttribPointer(0, 4, GL_FLOAT, GL_FALSE, 0, NULL);
> +
> +	glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
> +
> +	glDisableVertexAttribArray(0);
> +	glDeleteBuffers(1,&vbo);
> +}
> +
> +static GLboolean
> +probe_pixel(int unit, int x, int y)
> +{
> +	float expected[3];
> +
> +	get_texture_color(unit, expected);
> +
> +	if (piglit_probe_pixel_rgb(x, y, expected))
> +		return GL_TRUE;
> +
> +	printf("  When testing texture unit %i\n", unit);
> +	return GL_FALSE;
> +}
> +
> +enum piglit_result
> +piglit_display(void)
> +{
> +	GLboolean pass = GL_TRUE;
> +	int i, unit, x, y;
> +
> +	glClear(GL_COLOR_BUFFER_BIT);
> +
> +	x = 0;
> +	y = 0;
> +	unit = 0;
> +
> +	set_uniform(prog, "fragment_index", max_fs_textures);
> +	for (i = 0; i<  max_vs_textures; i++) {
> +		set_uniform(prog, "vertex_index", i);
> +		draw_rect_core(x, y, 20, 20);
> +		pass = probe_pixel(unit, x+10, y+10)&&  pass;
> +
> +		unit++;
> +		x += 20;
> +		if (x+20>  piglit_width) {
> +			x = 0;
> +			y += 20;
> +		}
> +	}
> +
> +	set_uniform(prog, "vertex_index", max_vs_textures);
> +	for (i = 0; i<  max_fs_textures; i++) {
> +		set_uniform(prog, "fragment_index", i);
> +		draw_rect_core(x, y, 20, 20);
> +		pass = probe_pixel(unit, x+10, y+10)&&  pass;
> +
> +		unit++;
> +		x += 20;
> +		if (x+20>  piglit_width) {
> +			x = 0;
> +			y += 20;
> +		}
> +	}
> +
> +	piglit_check_gl_error(GL_NO_ERROR);
> +	piglit_present_results();
> +
> +	return pass ? PIGLIT_PASS : PIGLIT_FAIL;
> +}
> +
> +static void
> +set_texture(int unit)
> +{
> +	GLuint tex;
> +	float color[3];
> +
> +	get_texture_color(unit, color);
> +
> +	glGenTextures(1,&tex);
> +	glActiveTexture(GL_TEXTURE0 + unit);
> +	glBindTexture(GL_TEXTURE_2D, tex);
> +	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB8, 1, 1, 0,
> +		     GL_RGB, GL_FLOAT, color);
> +	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
> +	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
> +
> +	piglit_check_gl_error(GL_NO_ERROR);
> +}
> +
> +void
> +piglit_init(int argc, char **argv)
> +{
> +	GLuint vs, fs, vao;
> +	int max_combined_textures, i, unit;
> +	char str[2048];
> +
> +	/* get limits */
> +	glGetIntegerv(GL_MAX_TEXTURE_IMAGE_UNITS,&max_fs_textures);
> +	glGetIntegerv(GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS,&max_vs_textures);
> +	glGetIntegerv(GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS,&max_combined_textures);
> +	assert(max_fs_textures<= max_combined_textures);
> +
> +	max_vs_textures = MIN2(max_vs_textures, max_combined_textures - max_fs_textures);
> +
> +	/* compile shaders */
> +	if (max_vs_textures) {
> +		sprintf(str, vs_source, max_vs_textures);
> +		vs = piglit_compile_shader_text(GL_VERTEX_SHADER, str);
> +	}
> +	else {
> +		vs = piglit_compile_shader_text(GL_VERTEX_SHADER, vs_source_no_textures);
> +	}
> +
> +	sprintf(str, fs_source, max_fs_textures);
> +	fs = piglit_compile_shader_text(GL_FRAGMENT_SHADER, str);
> +
> +	prog = piglit_link_simple_program(vs, fs);
> +	glUseProgram(prog);
> +
> +	piglit_check_gl_error(GL_NO_ERROR);
> +
> +	/* initialize textures */
> +	unit = 0;
> +	for (i = 0; i<  max_vs_textures; i++) {
> +		char name[64];
> +		sprintf(name, "vertex_tex[%i]", i);
> +		set_uniform(prog, name, unit);
> +		set_texture(unit);
> +		unit++;
> +	}
> +
> +	for (i = 0; i<  max_fs_textures; i++) {
> +		char name[64];
> +		sprintf(name, "fragment_tex[%i]", i);
> +		set_uniform(prog, name, unit);
> +		set_texture(unit);
> +		unit++;
> +	}
> +
> +	glClearColor(0.0, 0.0, 1.0, 1.0);
> +	glGenVertexArrays(1,&vao);
> +	glBindVertexArray(vao);
> +
> +	piglit_check_gl_error(GL_NO_ERROR);
> +}

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

BTW, I tried to test this with NVIDIA's driver but it appears that 
piglit can't create a GL 3.1 context:

$ bin/gl-3.1-max-samplers -auto
piglit: info: Failed to create GL 3.1 core context
piglit: info: Failed to create any GL context
PIGLIT: {'result': 'skip' }


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