ngl: Improve the gradient shaders

Use a define for MAX_COLOR_STOPS, and give the loop
a fixed limit.
This commit is contained in:
Matthias Clasen 2021-03-13 17:54:15 -05:00
parent 3f60c39de4
commit c1f98d6837
3 changed files with 48 additions and 30 deletions

View File

@ -18,6 +18,8 @@ void main() {
// FRAGMENT_SHADER:
// conic_gradient.glsl
#define MAX_COLOR_STOPS 6
#ifdef GSK_LEGACY
uniform int u_num_color_stops;
#else
@ -25,7 +27,7 @@ uniform highp int u_num_color_stops; // Why? Because it works like this.
#endif
uniform vec4 u_geometry;
uniform float u_color_stops[6 * 5];
uniform float u_color_stops[MAX_COLOR_STOPS * 5];
_NOPERSPECTIVE_ _IN_ vec2 coord;
@ -50,27 +52,31 @@ void main() {
// fract() does the modulo here, so now we have progress
// into the current conic
float offset = fract(angle * u_geometry.z + u_geometry.w);
float curr_offset;
float next_offset;
if (offset < get_offset(0)) {
next_offset = get_offset(0);
if (offset < next_offset) {
gskSetOutputColor(gsk_scaled_premultiply(get_color(0), u_alpha));
return;
}
int n = u_num_color_stops - 1;
for (int i = 0; i < n; i++) {
float curr_offset = get_offset(i);
float next_offset = get_offset(i + 1);
if (offset >= get_offset(u_num_color_stops - 1)) {
gskSetOutputColor(gsk_scaled_premultiply(get_color(u_num_color_stops - 1), u_alpha));
return;
}
if (offset >= curr_offset && offset < next_offset) {
for (int i = 0; i < MAX_COLOR_STOPS; i++) {
curr_offset = next_offset;
next_offset = get_offset(i + 1);
if (offset < next_offset) {
float f = (offset - curr_offset) / (next_offset - curr_offset);
vec4 curr_color = gsk_premultiply(get_color(i));
vec4 next_color = gsk_premultiply(get_color(i + 1));
vec4 color = mix(curr_color, next_color, f);
gskSetOutputColor(color * u_alpha);
return;
}
}
gskSetOutputColor(gsk_scaled_premultiply(get_color(n), u_alpha));
}

View File

@ -42,13 +42,15 @@ void main() {
// FRAGMENT_SHADER:
// linear_gradient.glsl
#define MAX_COLOR_STOPS 6
#ifdef GSK_LEGACY
uniform int u_num_color_stops;
#else
uniform highp int u_num_color_stops; // Why? Because it works like this.
#endif
uniform float u_color_stops[6 * 5];
uniform float u_color_stops[MAX_COLOR_STOPS * 5];
uniform bool u_repeat;
_NOPERSPECTIVE_ _IN_ vec4 info;
@ -68,31 +70,35 @@ vec4 get_color(int index) {
void main() {
float offset = dot(info.xy, info.zw);
float curr_offset;
float next_offset;
if (u_repeat) {
offset = fract(offset);
}
if (offset < get_offset(0)) {
next_offset = get_offset(0);
if (offset < next_offset) {
gskSetOutputColor(gsk_scaled_premultiply(get_color(0), u_alpha));
return;
}
int n = u_num_color_stops - 1;
for (int i = 0; i < n; i++) {
float curr_offset = get_offset(i);
float next_offset = get_offset(i + 1);
if (offset >= get_offset(u_num_color_stops - 1)) {
gskSetOutputColor(gsk_scaled_premultiply(get_color(u_num_color_stops - 1), u_alpha));
return;
}
if (offset >= curr_offset && offset < next_offset) {
for (int i = 0; i < MAX_COLOR_STOPS; i++) {
curr_offset = next_offset;
next_offset = get_offset(i + 1);
if (offset < next_offset) {
float f = (offset - curr_offset) / (next_offset - curr_offset);
vec4 curr_color = gsk_premultiply(get_color(i));
vec4 next_color = gsk_premultiply(get_color(i + 1));
vec4 color = mix(curr_color, next_color, f);
gskSetOutputColor(color * u_alpha);
return;
}
}
gskSetOutputColor(gsk_scaled_premultiply(get_color(n), u_alpha));
}

View File

@ -20,6 +20,8 @@ void main() {
// FRAGMENT_SHADER:
// radial_gradient.glsl
#define MAX_COLOR_STOPS 6
#ifdef GSK_LEGACY
uniform int u_num_color_stops;
#else
@ -28,7 +30,7 @@ uniform highp int u_num_color_stops;
uniform bool u_repeat;
uniform vec2 u_range;
uniform float u_color_stops[6 * 5];
uniform float u_color_stops[MAX_COLOR_STOPS * 5];
_NOPERSPECTIVE_ _IN_ vec2 coord;
@ -48,31 +50,35 @@ vec4 get_color(int index) {
void main() {
// Reverse scale
float offset = length(coord) * u_range.x + u_range.y;
float curr_offset;
float next_offset;
if (u_repeat) {
offset = fract(offset);
}
if (offset < get_offset(0)) {
next_offset = get_offset(0);
if (offset < next_offset) {
gskSetOutputColor(gsk_scaled_premultiply(get_color(0), u_alpha));
return;
}
int n = u_num_color_stops - 1;
for (int i = 0; i < n; i++) {
float curr_offset = get_offset(i);
float next_offset = get_offset(i + 1);
if (offset >= get_offset(u_num_color_stops - 1)) {
gskSetOutputColor(gsk_scaled_premultiply(get_color(u_num_color_stops - 1), u_alpha));
return;
}
if (offset >= curr_offset && offset < next_offset) {
for (int i = 0; i < MAX_COLOR_STOPS; i++) {
curr_offset = next_offset;
next_offset = get_offset(i + 1);
if (offset < next_offset) {
float f = (offset - curr_offset) / (next_offset - curr_offset);
vec4 curr_color = gsk_premultiply(get_color(i));
vec4 next_color = gsk_premultiply(get_color(i + 1));
vec4 color = mix(curr_color, next_color, f);
gskSetOutputColor(color * u_alpha);
return;
}
}
gskSetOutputColor(gsk_scaled_premultiply(get_color(n), u_alpha));
}