[Glamor] [PATCH 5/7] Fix the problem of vertical and horizontal case error in linear gradient.

[Zhigang Gong]

On Tue, May 08, 2012 at 08:45:03AM +0800, junyan.he at linux.intel.com wrote:
> From: Junyan He <junyan.he at linux.intel.com>
> 
>  1. The vertical and horizontal judgement in linear
>  gradient have problem when p1 point and p2 point
>  distance is very small but the gradient pict have a
>  transform matrix which will convert the X Y coordinates
>  to small values. So the judgement is not suitable.
>  Because this judgement's purpose is to assure the
>  divisor not to be zero, so we simply it to enter
>  horizontal judgement when p1 and p2's Y is same.
>  Vertical case is deleted.
If we have non-int transform matrix, both the vertical and
horizontal check are invalid here, right? You may need to
check whether we have a non-int transform matrix, and then
choose different method to check the hor/vert condition?
>  2. Delete the unused p1 p2 uniform variable.
> 
> 
> Signed-off-by: Junyan He <junyan.he at linux.intel.com>
> ---
>  src/glamor_gradient.c |   28 ++++------------------------
>  1 files changed, 4 insertions(+), 24 deletions(-)
> 
> diff --git a/src/glamor_gradient.c b/src/glamor_gradient.c
> index 7263c2b..12eff03 100644
> --- a/src/glamor_gradient.c
> +++ b/src/glamor_gradient.c
> @@ -491,8 +491,6 @@ _glamor_create_linear_gradient_program(ScreenPtr screen, int stops_count, int dy
>  	    "uniform mat3 transform_mat;\n"
>  	    "uniform int repeat_type;\n"
>  	    "uniform int hor_ver;\n"
> -	    "uniform vec4 pt1;\n"
> -	    "uniform vec4 pt2;\n"
>  	    "uniform float pt_slope;\n"
>  	    "uniform float cos_val;\n"
>  	    "uniform float p1_distance;\n"
> @@ -529,10 +527,6 @@ _glamor_create_linear_gradient_program(ScreenPtr screen, int stops_count, int dy
>  	    "        distance = source_texture_trans.x;\n"
>  	    "        _p1_distance = p1_distance * source_texture_trans.z;\n"
>  	    "        _pt_distance = pt_distance * source_texture_trans.z;\n"
> -	    "    } else if (hor_ver == 2) {\n"//vertical case.
> -	    "        distance = source_texture_trans.y;\n"
> -	    "        _p1_distance = p1_distance * source_texture_trans.z;\n"
> -	    "        _pt_distance = pt_distance * source_texture_trans.z;\n"
>  	    "    } \n"
>  	    "    \n"
>  	    "    distance = distance - _p1_distance; \n"
> @@ -1301,8 +1295,6 @@ glamor_generate_linear_gradient_picture(ScreenPtr screen,
>  	GLfloat n_stops_st[LINEAR_SMALL_STOPS];
>  
>  	GLint transform_mat_uniform_location;
> -	GLint pt1_uniform_location;
> -	GLint pt2_uniform_location;
>  	GLint n_stop_uniform_location;
>  	GLint stops_uniform_location;
>  	GLint stop0_uniform_location;
> @@ -1369,10 +1361,6 @@ glamor_generate_linear_gradient_picture(ScreenPtr screen,
>  	}
>  
>  	/* Bind all the uniform vars .*/
> -	pt1_uniform_location =
> -	    dispatch->glGetUniformLocation(gradient_prog, "pt1");
> -	pt2_uniform_location =
> -	    dispatch->glGetUniformLocation(gradient_prog, "pt2");
>  	n_stop_uniform_location =
>  	    dispatch->glGetUniformLocation(gradient_prog, "n_stop");
>  	pt_slope_uniform_location =
> @@ -1460,7 +1448,6 @@ glamor_generate_linear_gradient_picture(ScreenPtr screen,
>  	                        y_source,
>  	                        glamor_priv->yInverted,
>  	                        pt1);
> -	dispatch->glUniform4fv(pt1_uniform_location, 1, pt1);
>  	DEBUGF("pt1:(%f %f)\n", pt1[0], pt1[1]);
>  
>  	glamor_set_normalize_pt(xscale, yscale,
> @@ -1470,7 +1457,6 @@ glamor_generate_linear_gradient_picture(ScreenPtr screen,
>  	                        y_source,
>  	                        glamor_priv->yInverted,
>  	                        pt2);
> -	dispatch->glUniform4fv(pt2_uniform_location, 1, pt2);
>  	DEBUGF("pt2:(%f %f)\n", pt2[0], pt2[1]);
>  
>  	/* Set all the stops and colors to shader. */
> @@ -1545,22 +1531,16 @@ glamor_generate_linear_gradient_picture(ScreenPtr screen,
>  		dispatch->glUniform1i(n_stop_uniform_location, count);
>  	}
>  
> -	if (abs((pt2[1] - pt1[1]) / yscale) < 1.0) { // The horizontal case.
> +	if (src_picture->pSourcePict->linear.p2.y ==
> +	              src_picture->pSourcePict->linear.p1.y) { // The horizontal case.
>  		dispatch->glUniform1i(hor_ver_uniform_location, 1);
> -		DEBUGF("p1.x: %f, p2.x: %f, enter the horizontal case\n", pt1[1], pt2[1]);
> +		DEBUGF("p1.y: %f, p2.y: %f, enter the horizontal case\n",
> +		       pt1[1], pt2[1]);
>  
>  		p1_distance = pt1[0];
>  		pt_distance = (pt2[0] - p1_distance);
>  		dispatch->glUniform1f(p1_distance_uniform_location, p1_distance);
>  		dispatch->glUniform1f(pt_distance_uniform_location, pt_distance);
> -	} else if (abs((pt2[0] - pt1[0]) / xscale) < 1.0) { //The vertical case.
> -		dispatch->glUniform1i(hor_ver_uniform_location, 2);
> -		DEBUGF("p1.y: %f, p2.y: %f, enter the vertical case\n", pt1[0], pt2[0]);
> -
> -		p1_distance = pt1[1];
> -		pt_distance = (pt2[1] - p1_distance);
> -		dispatch->glUniform1f(p1_distance_uniform_location, p1_distance);
> -		dispatch->glUniform1f(pt_distance_uniform_location, pt_distance);
>  	} else {
>  		/* The slope need to compute here. In shader, the viewport set will change
>  		   the orginal slope and the slope which is vertical to it will not be correct.*/
> -- 
> 1.7.7.6
>