[Piglit] [PATCH 03/18] util: Draw rectangles using triangle strips instead of quads.

[Brian Paul]

On 06/03/2013 06:39 AM, Fabian Bieler wrote:
> This is usefull for core profile OpenGL contexts and geometry shaders.
> ---
>   tests/util/piglit-util-gl.c | 22 +++++++++++-----------
>   1 file changed, 11 insertions(+), 11 deletions(-)
>
> diff --git a/tests/util/piglit-util-gl.c b/tests/util/piglit-util-gl.c
> index 0a56582..04c36bb 100644
> --- a/tests/util/piglit-util-gl.c
> +++ b/tests/util/piglit-util-gl.c
> @@ -855,11 +855,11 @@ piglit_draw_rect(float x, float y, float w, float h)
>   	verts[1][1] = y;
>   	verts[1][2] = 0.0;
>   	verts[1][3] = 1.0;
> -	verts[2][0] = x + w;
> +	verts[2][0] = x;
>   	verts[2][1] = y + h;
>   	verts[2][2] = 0.0;
>   	verts[2][3] = 1.0;
> -	verts[3][0] = x;
> +	verts[3][0] = x + w;
>   	verts[3][1] = y + h;
>   	verts[3][2] = 0.0;
>   	verts[3][3] = 1.0;
> @@ -867,7 +867,7 @@ piglit_draw_rect(float x, float y, float w, float h)
>   	glVertexPointer(4, GL_FLOAT, 0, verts);
>   	glEnableClientState(GL_VERTEX_ARRAY);
>
> -	glDrawArrays(GL_QUADS, 0, 4);
> +	glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
>
>   	glDisableClientState(GL_VERTEX_ARRAY);
>   }
> @@ -888,11 +888,11 @@ piglit_draw_rect_z(float z, float x, float y, float w, float h)
>   	verts[1][1] = y;
>   	verts[1][2] = z;
>   	verts[1][3] = 1.0;
> -	verts[2][0] = x + w;
> +	verts[2][0] = x;
>   	verts[2][1] = y + h;
>   	verts[2][2] = z;
>   	verts[2][3] = 1.0;
> -	verts[3][0] = x;
> +	verts[3][0] = x + w;
>   	verts[3][1] = y + h;
>   	verts[3][2] = z;
>   	verts[3][3] = 1.0;
> @@ -900,7 +900,7 @@ piglit_draw_rect_z(float z, float x, float y, float w, float h)
>   	glVertexPointer(4, GL_FLOAT, 0, verts);
>   	glEnableClientState(GL_VERTEX_ARRAY);
>
> -	glDrawArrays(GL_QUADS, 0, 4);
> +	glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
>
>   	glDisableClientState(GL_VERTEX_ARRAY);
>   }
> @@ -928,17 +928,17 @@ piglit_draw_rect_tex(float x, float y, float w, float h,
>   	verts[1][3] = 1.0;
>   	tex[1][0] = tx + tw;
>   	tex[1][1] = ty;
> -	verts[2][0] = x + w;
> +	verts[2][0] = x;
>   	verts[2][1] = y + h;
>   	verts[2][2] = 0.0;
>   	verts[2][3] = 1.0;
> -	tex[2][0] = tx + tw;
> +	tex[2][0] = tx;
>   	tex[2][1] = ty + th;
> -	verts[3][0] = x;
> +	verts[3][0] = x + w;
>   	verts[3][1] = y + h;
>   	verts[3][2] = 0.0;
>   	verts[3][3] = 1.0;
> -	tex[3][0] = tx;
> +	tex[3][0] = tx + tw;
>   	tex[3][1] = ty + th;
>
>   	glVertexPointer(4, GL_FLOAT, 0, verts);
> @@ -946,7 +946,7 @@ piglit_draw_rect_tex(float x, float y, float w, float h,
>   	glEnableClientState(GL_VERTEX_ARRAY);
>   	glEnableClientState(GL_TEXTURE_COORD_ARRAY);
>
> -	glDrawArrays(GL_QUADS, 0, 4);
> +	glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
>
>   	glDisableClientState(GL_VERTEX_ARRAY);
>   	glDisableClientState(GL_TEXTURE_COORD_ARRAY);
>

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