[Piglit] [PATCH 10/20] msaa: Add ColorGradientSunburst program.

[Anuj Phogat]

On Tue, Jun 5, 2012 at 5:03 PM, Paul Berry <stereotype441 at gmail.com> wrote:
> This patch adds a new program to the common infrastructure for MSAA
> tests, ColorGradientSunburst, which draws a triangle sunburst where
> the color of each triangle is a gradient.  This program will be used
> to verify proper operation of MSAA when applied to color buffer
> formats.
> ---
>  tests/spec/ext_framebuffer_multisample/common.cpp |   52 +++++++++++++++++----
>  tests/spec/ext_framebuffer_multisample/common.h   |   13 +++++
>  2 files changed, 56 insertions(+), 9 deletions(-)
>
> diff --git a/tests/spec/ext_framebuffer_multisample/common.cpp b/tests/spec/ext_framebuffer_multisample/common.cpp
> index ac23683..0ded77b 100644
> --- a/tests/spec/ext_framebuffer_multisample/common.cpp
> +++ b/tests/spec/ext_framebuffer_multisample/common.cpp
> @@ -839,11 +839,13 @@ void Points::draw(float (*proj)[4])
>
>  void Sunburst::compile()
>  {
> -       /* Triangle coords within (-1,-1) to (1,1) rect */
> -       static const float pos_within_tri[][2] = {
> -               { -0.3, -0.8 },
> -               {  0.0,  1.0 },
> -               {  0.3, -0.8 }
> +       static struct vertex_attributes {
> +               float pos_within_tri[2];
> +               float barycentric_coords[3];
> +       } vertex_data[] = {
> +               { { -0.3, -0.8 }, { 1, 0, 0 } },
> +               { {  0.0,  1.0 }, { 0, 1, 0 } },
> +               { {  0.3, -0.8 }, { 0, 0, 1 } }
>        };
>
>        /* Total number of triangles drawn */
> @@ -852,6 +854,8 @@ void Sunburst::compile()
>        static const char *vert =
>                "#version 130\n"
>                "in vec2 pos_within_tri;\n"
> +               "in vec3 in_barycentric_coords;\n"
> +               "out vec3 barycentric_coords;\n"
>                "uniform float rotation;\n"
>                "uniform float depth;\n"
>                "uniform mat4 proj;\n"
> @@ -862,13 +866,17 @@ void Sunburst::compile()
>                "  pos = mat2(cos(rotation), sin(rotation),\n"
>                "             -sin(rotation), cos(rotation)) * pos;\n"
>                "  gl_Position = proj * vec4(pos, depth, 1.0);\n"
> +               "  barycentric_coords = in_barycentric_coords;\n"
>                "}\n";
>
>        static const char *frag =
>                "#version 130\n"
> +               "in vec3 barycentric_coords;\n"
> +               "uniform mat3x4 draw_colors;\n"
> +               "\n"
>                "void main()\n"
>                "{\n"
> -               "  gl_FragColor = vec4(0.0);\n"
> +               "  gl_FragColor = draw_colors * barycentric_coords;\n"
>                "}\n";
>
>        /* Compile program */
> @@ -878,6 +886,7 @@ void Sunburst::compile()
>        GLint fs = piglit_compile_shader_text(GL_FRAGMENT_SHADER, frag);
>        glAttachShader(prog, fs);
>        glBindAttribLocation(prog, 0, "pos_within_tri");
> +       glBindAttribLocation(prog, 1, "in_barycentric_coords");
>        glLinkProgram(prog);
>        if (!piglit_link_check_status(prog)) {
>                piglit_report_result(PIGLIT_FAIL);
> @@ -889,6 +898,7 @@ void Sunburst::compile()
>        depth_loc = glGetUniformLocation(prog, "depth");
>        glUniform1f(depth_loc, 0.0);
>        proj_loc = glGetUniformLocation(prog, "proj");
> +       draw_colors_loc = glGetUniformLocation(prog, "draw_colors");
>
>        /* Set up vertex array object */
>        glGenVertexArrays(1, &vao);
> @@ -897,11 +907,35 @@ void Sunburst::compile()
>        /* Set up vertex input buffer */
>        glGenBuffers(1, &vertex_buf);
>        glBindBuffer(GL_ARRAY_BUFFER, vertex_buf);
> -       glBufferData(GL_ARRAY_BUFFER, sizeof(pos_within_tri), pos_within_tri,
> +       glBufferData(GL_ARRAY_BUFFER, sizeof(vertex_data), vertex_data,
>                     GL_STATIC_DRAW);
>        glEnableVertexAttribArray(0);
> -       glVertexAttribPointer(0, ARRAY_SIZE(pos_within_tri[0]), GL_FLOAT,
> -                             GL_FALSE, sizeof(pos_within_tri[0]), (void *) 0);
> +       glVertexAttribPointer(0, ARRAY_SIZE(vertex_data[0].pos_within_tri),
> +                             GL_FLOAT, GL_FALSE, sizeof(vertex_data[0]),
> +                             (void *) 0);
> +       glEnableVertexAttribArray(1);
> +       glVertexAttribPointer(1, ARRAY_SIZE(vertex_data[0].barycentric_coords),
> +                             GL_FLOAT, GL_FALSE, sizeof(vertex_data[0]),
> +                             (void *) offsetof(vertex_attributes,
> +                                               barycentric_coords));
> +}
> +
> +void
> +ColorGradientSunburst::draw(const float (*proj)[4])
> +{
> +       glClear(GL_COLOR_BUFFER_BIT);
> +
> +       glUseProgram(prog);
> +       glUniformMatrix4fv(proj_loc, 1, GL_TRUE, &proj[0][0]);
> +       float draw_colors[3][4] =
> +               { { 1, 0, 0, 1.0 }, { 0, 1, 0, 0.5 }, { 0, 0, 1, 1.0 } };
> +       glUniformMatrix3x4fv(draw_colors_loc, 1, GL_FALSE,
> +                            &draw_colors[0][0]);
> +       glBindVertexArray(vao);
> +       for (int i = 0; i < num_tris; ++i) {
> +               glUniform1f(rotation_loc, M_PI * 2.0 * i / num_tris);
> +               glDrawArrays(GL_TRIANGLES, 0, 3);
> +       }
>  }
>
>  void
> diff --git a/tests/spec/ext_framebuffer_multisample/common.h b/tests/spec/ext_framebuffer_multisample/common.h
> index 2ea3b42..1287fc0 100644
> --- a/tests/spec/ext_framebuffer_multisample/common.h
> +++ b/tests/spec/ext_framebuffer_multisample/common.h
> @@ -251,6 +251,7 @@ protected:
>        GLint rotation_loc;
>        GLint depth_loc;
>        GLint proj_loc;
> +       GLint draw_colors_loc;
>        GLuint vao;
>        int num_tris;
>
> @@ -259,6 +260,18 @@ private:
>  };
>
>  /**
> + * Program that draws a test pattern into the color buffer.
> + *
> + * This program draws triangles using a variety of colors and
> + * gradients.
> + */
> +class ColorGradientSunburst : public Sunburst
> +{
> +public:
> +       virtual void draw(const float (*proj)[4]);
> +};
> +
> +/**
>  * Program we use to draw a test pattern into the stencil buffer.
>  *
>  * The triangles in this sunburst are drawn back-to-front, using no
> --
> 1.7.7.6
>

Reviewed-by: Anuj Phogat <anuj.phogat at gmail.com>