[Piglit] [PATCH] Test case on rendering with only fragment shader but no vertex shader.

Paul Berry stereotype441 at gmail.com
Tue Nov 1 09:19:46 PDT 2011


Before I get to specific comments, are you familiar with Piglit's "shader
runner" framework (look at any of the Piglit files that end in
".shader_test").  It seems like this test could be rewritten as a shader
runner test--that would make it shorter and more readable, and save a
compilation step.

Other comments follow...

On 1 November 2011 03:59, <jian.j.zhao at intel.com> wrote:

> From: Jian Zhao <jian.j.zhao at intel.com>
>
> Per the GL C Specification on glLinkProgram, it should use fixed function
> pipeline if there is no vertex shader or fragment shader. The spec is as
> following:
>        "If program contains shader objects
>        of type GL_VERTEX_SHADER but does not
>        contain shader objects of type
>        GL_FRAGMENT_SHADER, the vertex shader will
>        be linked against the implicit interface for fixed functionality
>        fragment processing. Similarly, if
>        program contains shader objects of type
>        GL_FRAGMENT_SHADER but it does not contain
>        shader objects of type GL_VERTEX_SHADER,
>        the fragment shader will be linked against the implicit
>        interface for fixed functionality vertex processing."
>

When quoting from the spec, can you site the particular version of the GL
spec that you're quoting, and the section number you're quoting from?  That
will make it easier to figure out what went wrong if this test ever fails.


> ---
>  tests/shaders/CMakeLists.gl.txt                |    1 +
>  tests/shaders/glsl-no-vertex-shader-compiled.c |  165
> ++++++++++++++++++++++++
>  2 files changed, 166 insertions(+), 0 deletions(-)
>  create mode 100644 tests/shaders/glsl-no-vertex-shader-compiled.c
>
> diff --git a/tests/shaders/CMakeLists.gl.txt
> b/tests/shaders/CMakeLists.gl.txt
> index 3dce256..d009395 100644
> --- a/tests/shaders/CMakeLists.gl.txt
> +++ b/tests/shaders/CMakeLists.gl.txt
> @@ -28,6 +28,7 @@ add_executable (fp-condition_codes-01
> fp-condition_codes-01.c)
>  add_executable (fp-lit-mask fp-lit-mask.c)
>  add_executable (fp-lit-src-equals-dst fp-lit-src-equals-dst.c)
>  add_executable (fp-fog fp-fog.c)
> +add_executable (glsl-no-vertex-shader-compiled
> glsl-no-vertex-shader-compiled.c)
>  add_executable (fp-formats fp-formats.c)
>  add_executable (fp-fragment-position fp-fragment-position.c)
>  add_executable (fp-generic fp-generic.c)
> diff --git a/tests/shaders/glsl-no-vertex-shader-compiled.c
> b/tests/shaders/glsl-no-vertex-shader-compiled.c
> new file mode 100644
> index 0000000..0f90f6b
> --- /dev/null
> +++ b/tests/shaders/glsl-no-vertex-shader-compiled.c
> @@ -0,0 +1,165 @@
> +/*
> + * Copyright © 2011 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:
> + *    Jian Zhao <jian.j.zhao at intel.com>
> + *
> + */
> +
> +/** @file glsl-no-vertex-shader-compiled.c
> + *
> + * Tests that OpenGL shader should work well when only have fragment
> shader(or vertext shader), but now if without vertext shader it doesn't
> work.
> +   In the OpenGL spec for glLinkProgram, as following says:
> +   "If program contains shader objects
> +       of type GL_VERTEX_SHADER but does not
> +       contain shader objects of type
> +       GL_FRAGMENT_SHADER, the vertex shader will
> +       be linked against the implicit interface for fixed functionality
> +       fragment processing. Similarly, if
> +       program contains shader objects of type
> +       GL_FRAGMENT_SHADER but it does not contain
> +       shader objects of type GL_VERTEX_SHADER,
> +       the fragment shader will be linked against the implicit
> +       interface for fixed functionality vertex processing."
> + *
> + */
> +
> +#include "piglit-util.h"
> +#include "piglit-framework.h"
> +
> +int piglit_width = 100, piglit_height = 100;
> +int piglit_window_mode = GLUT_RGBA | GLUT_DOUBLE;
> +
> +static GLint prog;
> +
> +static const char fs_vector_template[] =
> +"#version 120\n"
> +"void myfunc2(void); \n"
> +"void myfunc3(void); \n"
> +"void main() \n"
> +"{ \n"
> +"    gl_FragColor = gl_Color; \n"
> +"    myfunc2(); \n"
> +"} \n"
> +"void myfunc2(void) \n"
> +"{ \n"
> +"     gl_FragColor = vec4(0.2,0.2,0.2, 1.0); \n"
> +"     myfunc3(); \n"
> +"} \n"
> +"void myfunc3(void) \n"
> +"{ \n"
> +"     gl_FragColor = vec4(0.2,0.8,0.2,1.0); \n"
> +"} \n";
> +
>

Are you trying to test something about the behavior of function calls
here?  If so, that should be split into its own test, with a comment
explaining what you're trying to accomplish.  If not, we should use the
simplest possible fragment shader that allows us to test what we're trying
to test, e.g.:

void main()
{
  gl_FragColor = vec4(0.2, 0.8, 0.2, 1.0);
}


> +
> +enum piglit_result
> +piglit_display(void)
> +{
> +       GLboolean result = PIGLIT_PASS;
> +       GLfloat expectedColor[4] = {0.2, 0.8, 0.2, 1.0};
> +
> +       glClearColor(1.0, 0.1, 0.1, 0.0);
> +       glClear(GL_COLOR_BUFFER_BIT );
> +
> +       glColor4f(0.0, 1.0, 0.0, 0.0);
> +       glBegin(GL_QUADS);
> +       glVertex3f(0.0, 0.0, 0.0);
> +       glVertex3f(0.5, 0.0, 0.0);
> +       glVertex3f(0.5, 0.5, 0.0);
> +       glVertex3f(0.0, 0.5, 0.0);
> +       glEnd();
> +
> +       result = piglit_probe_pixel_rgba(piglit_width /2, piglit_height /
> 2,
> +                                       expectedColor) ? PIGLIT_PASS :
> PIGLIT_FAIL;
> +       glutSwapBuffers();
> +
> +       return result;
> +}
> +
> +static GLuint compile_shader(GLenum shaderType, const char * text)
> +{
> +        GLuint shader;
> +        GLint status;
> +
> +        shader = glCreateShaderObjectARB(shaderType);
> +        glShaderSourceARB(shader, 1, (const GLchar **)&text, NULL);
> +        glCompileShaderARB(shader);
> +
> +        glGetObjectParameterivARB(shader, GL_OBJECT_COMPILE_STATUS_ARB,
> &status);
> +       if (!status) {
> +                GLchar log[1000];
> +                GLsizei len;
> +                glGetInfoLogARB(shader, 1000, &len, log);
> +                fprintf(stderr, "Error: problem compiling shader: %s\n",
> log);
> +                piglit_report_result(PIGLIT_FAIL);
> +        }
> +
> +        return shader;
> +}
> +
> +static GLuint link_program(GLuint fs)
> +{
> +        GLuint program;
> +        GLint status;
> +
> +        program = glCreateProgramObjectARB();
> +
> +        if (fs)
> +                glAttachObjectARB(program, fs);
> +
> +        glLinkProgramARB(program);
> +        glGetObjectParameterivARB(program, GL_OBJECT_LINK_STATUS_ARB,
> &status);
> +        if (!status) {
> +                GLchar log[1000];
> +                GLsizei len;
> +                glGetInfoLogARB(program, 1000, &len, log);
> +                fprintf(stderr, "Error: problem linking program: %s\n",
> log);
> +                piglit_report_result(PIGLIT_FAIL);
> +        }
> +
> +        return program;
> +}
> +
> +void
> +piglit_init(int argc, char **argv)
> +{
> +       GLint fs;
> +       char *fs_buffer;
> +
> +       if (!GLEW_VERSION_2_0 || !GLEW_ARB_shader_objects ||
> !GLEW_ARB_vertex_shader || !GLEW_ARB_fragment_shader) {
> +                printf("Requires ARB_shader_objects and
> ARB_{vertex,fragment}_shader\n");
> +                piglit_report_result(PIGLIT_SKIP);
> +        }
> +
> +       piglit_ortho_projection(piglit_width, piglit_height, GL_FALSE);
> +
> +       fs_buffer = (char *) malloc(sizeof(char) *
> (strlen(fs_vector_template)+1));
> +       strcpy(fs_buffer, fs_vector_template);
> +       fs = compile_shader(GL_FRAGMENT_SHADER_ARB, fs_buffer);
> +
> +       prog = link_program(fs);
> +
> +       glUseProgramObjectARB(prog);
> +
> +       if(fs_buffer)
> +               free(fs_buffer);
> +}
> --
> 1.7.0.1
>
>
> _______________________________________________
> Piglit mailing list
> Piglit at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/piglit
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.freedesktop.org/archives/piglit/attachments/20111101/3add2e35/attachment.htm>


More information about the Piglit mailing list