From 5c439f4e9ca040dc16899e50a3cb3b6172cb9b83 Mon Sep 17 00:00:00 2001 From: "Jasper St. Pierre" Date: Wed, 28 Nov 2012 16:51:42 -0500 Subject: [PATCH] scroll-view-fade: Do the offset math in the shader This doesn't (or shouldn't) change the visual appearance of the fade effect, but does do all the testing math inside the shader, rather than on the CPU. This will make fading the offset much easier in the future. https://bugzilla.gnome.org/show_bug.cgi?id=689249 --- src/st/st-scroll-view-fade.c | 76 ++++++++++++++------------------- src/st/st-scroll-view-fade.glsl | 25 ++++++----- 2 files changed, 44 insertions(+), 57 deletions(-) diff --git a/src/st/st-scroll-view-fade.c b/src/st/st-scroll-view-fade.c index 5093e7d19..1a9ff1db3 100644 --- a/src/st/st-scroll-view-fade.c +++ b/src/st/st-scroll-view-fade.c @@ -53,10 +53,10 @@ struct _StScrollViewFade gint height_uniform; gint width_uniform; gint fade_area_uniform; - gint offset_top_uniform; - gint offset_bottom_uniform; - gint offset_left_uniform; - gint offset_right_uniform; + gint vfade_offset_uniform; + gint hfade_offset_uniform; + gint vvalue_uniform; + gint hvalue_uniform; StAdjustment *vadjustment; StAdjustment *hadjustment; @@ -121,14 +121,14 @@ st_scroll_view_fade_pre_paint (ClutterEffect *effect) cogl_program_get_uniform_location (self->program, "width"); self->fade_area_uniform = cogl_program_get_uniform_location (self->program, "fade_area"); - self->offset_top_uniform = - cogl_program_get_uniform_location (self->program, "offset_top"); - self->offset_bottom_uniform = - cogl_program_get_uniform_location (self->program, "offset_bottom"); - self->offset_left_uniform = - cogl_program_get_uniform_location (self->program, "offset_left"); - self->offset_right_uniform = - cogl_program_get_uniform_location (self->program, "offset_right"); + self->vfade_offset_uniform = + cogl_program_get_uniform_location (self->program, "vfade_offset"); + self->hfade_offset_uniform = + cogl_program_get_uniform_location (self->program, "hfade_offset"); + self->vvalue_uniform = + cogl_program_get_uniform_location (self->program, "vvalue"); + self->hvalue_uniform = + cogl_program_get_uniform_location (self->program, "hvalue"); } parent_class = CLUTTER_EFFECT_CLASS (st_scroll_view_fade_parent_class); @@ -207,38 +207,24 @@ st_scroll_view_fade_paint_target (ClutterOffscreenEffect *effect) if (h_scroll_visible) fade_area[1][1] -= clutter_actor_get_height (hscroll); - st_adjustment_get_values (self->vadjustment, &value, &lower, &upper, NULL, NULL, &page_size); + if (self->vvalue_uniform > -1) + { + st_adjustment_get_values (self->vadjustment, &value, &lower, &upper, NULL, NULL, &page_size); + value = (value - lower) / (upper - page_size - lower); + cogl_program_set_uniform_1f (self->program, self->vvalue_uniform, value); + } - if (self->offset_top_uniform > -1) { - if (value > lower + 0.1) - cogl_program_set_uniform_1f (self->program, self->offset_top_uniform, self->vfade_offset); - else - cogl_program_set_uniform_1f (self->program, self->offset_top_uniform, 0.0f); - } - - if (self->offset_bottom_uniform > -1) { - if (value < upper - page_size - 0.1) - cogl_program_set_uniform_1f (self->program, self->offset_bottom_uniform, self->vfade_offset); - else - cogl_program_set_uniform_1f (self->program, self->offset_bottom_uniform, 0.0f); - } - - st_adjustment_get_values (self->hadjustment, &value, &lower, &upper, NULL, NULL, &page_size); - - if (self->offset_left_uniform > -1) { - if (value > lower + 0.1) - cogl_program_set_uniform_1f (self->program, self->offset_left_uniform, self->hfade_offset); - else - cogl_program_set_uniform_1f (self->program, self->offset_left_uniform, 0.0f); - } - - if (self->offset_right_uniform > -1) { - if (value < upper - page_size - 0.1) - cogl_program_set_uniform_1f (self->program, self->offset_right_uniform, self->hfade_offset); - else - cogl_program_set_uniform_1f (self->program, self->offset_right_uniform, 0.0f); - } + if (self->hvalue_uniform > -1) + { + st_adjustment_get_values (self->hadjustment, &value, &lower, &upper, NULL, NULL, &page_size); + value = (value - lower) / (upper - page_size - lower); + cogl_program_set_uniform_1f (self->program, self->hvalue_uniform, value); + } + if (self->vfade_offset_uniform > -1) + cogl_program_set_uniform_1f (self->program, self->vfade_offset_uniform, self->vfade_offset); + if (self->hfade_offset_uniform > -1) + cogl_program_set_uniform_1f (self->program, self->hfade_offset_uniform, self->hfade_offset); if (self->tex_uniform > -1) cogl_program_set_uniform_1i (self->program, self->tex_uniform, 0); if (self->height_uniform > -1) @@ -517,8 +503,10 @@ st_scroll_view_fade_init (StScrollViewFade *self) self->height_uniform = -1; self->width_uniform = -1; self->fade_area_uniform = -1; - self->offset_top_uniform = -1; - self->offset_bottom_uniform = -1; + self->vfade_offset_uniform = -1; + self->hfade_offset_uniform = -1; + self->vvalue_uniform = -1; + self->hvalue_uniform = -1; self->vfade_offset = DEFAULT_FADE_OFFSET; self->hfade_offset = DEFAULT_FADE_OFFSET; diff --git a/src/st/st-scroll-view-fade.glsl b/src/st/st-scroll-view-fade.glsl index 4b07642ad..7897c7b80 100644 --- a/src/st/st-scroll-view-fade.glsl +++ b/src/st/st-scroll-view-fade.glsl @@ -22,10 +22,10 @@ uniform sampler2D tex; uniform float height; uniform float width; -uniform float offset_bottom; -uniform float offset_top; -uniform float offset_right; -uniform float offset_left; +uniform float vfade_offset; +uniform float hfade_offset; +uniform float vvalue; +uniform float hvalue; /* * Used to pass the fade area to the shader @@ -50,17 +50,16 @@ void main () return; float ratio = 1.0; - float fade_bottom_start = fade_area[1][1] - offset_bottom; - float fade_right_start = fade_area[1][0] - offset_right; - float ratio_top = y / offset_top; + float fade_bottom_start = fade_area[1][1] - vfade_offset; + float fade_right_start = fade_area[1][0] - hfade_offset; + float ratio_top = y / vfade_offset; float ratio_bottom = (fade_area[1][1] - y)/(fade_area[1][1] - fade_bottom_start); - float ratio_left = x / offset_left; + float ratio_left = x / hfade_offset; float ratio_right = (fade_area[1][0] - x)/(fade_area[1][0] - fade_right_start); - bool in_scroll_area = fade_area[0][0] <= x && fade_area[1][0] >= x; - bool fade_top = y < offset_top; - bool fade_bottom = y > fade_bottom_start; - bool fade_left = x < offset_left; - bool fade_right = x > fade_right_start; + bool fade_top = y < vfade_offset && vvalue > 0; + bool fade_bottom = y > fade_bottom_start && vvalue < 1; + bool fade_left = x < hfade_offset && hvalue > 0; + bool fade_right = x > fade_right_start && hvalue < 1; if (fade_top) { ratio *= ratio_top;