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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 19:33:14 +0000 |
commit | 36d22d82aa202bb199967e9512281e9a53db42c9 (patch) | |
tree | 105e8c98ddea1c1e4784a60a5a6410fa416be2de /gfx/wr/webrender/res/transform.glsl | |
parent | Initial commit. (diff) | |
download | firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.tar.xz firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.zip |
Adding upstream version 115.7.0esr.upstream/115.7.0esr
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'gfx/wr/webrender/res/transform.glsl')
-rw-r--r-- | gfx/wr/webrender/res/transform.glsl | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/gfx/wr/webrender/res/transform.glsl b/gfx/wr/webrender/res/transform.glsl new file mode 100644 index 0000000000..d068b26c0e --- /dev/null +++ b/gfx/wr/webrender/res/transform.glsl @@ -0,0 +1,140 @@ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +flat varying highp vec4 vTransformBounds; + +#ifdef WR_VERTEX_SHADER + +#define VECS_PER_TRANSFORM 8U +uniform HIGHP_SAMPLER_FLOAT sampler2D sTransformPalette; + +void init_transform_vs(vec4 local_bounds) { + vTransformBounds = local_bounds; +} + +struct Transform { + mat4 m; + mat4 inv_m; + bool is_axis_aligned; +}; + +Transform fetch_transform(int id) { + Transform transform; + + transform.is_axis_aligned = (id >> 23) == 0; + int index = id & 0x007fffff; + + // Create a UV base coord for each 8 texels. + // This is required because trying to use an offset + // of more than 8 texels doesn't work on some versions + // of macOS. + ivec2 uv = get_fetch_uv(index, VECS_PER_TRANSFORM); + ivec2 uv0 = ivec2(uv.x + 0, uv.y); + + transform.m[0] = TEXEL_FETCH(sTransformPalette, uv0, 0, ivec2(0, 0)); + transform.m[1] = TEXEL_FETCH(sTransformPalette, uv0, 0, ivec2(1, 0)); + transform.m[2] = TEXEL_FETCH(sTransformPalette, uv0, 0, ivec2(2, 0)); + transform.m[3] = TEXEL_FETCH(sTransformPalette, uv0, 0, ivec2(3, 0)); + + transform.inv_m[0] = TEXEL_FETCH(sTransformPalette, uv0, 0, ivec2(4, 0)); + transform.inv_m[1] = TEXEL_FETCH(sTransformPalette, uv0, 0, ivec2(5, 0)); + transform.inv_m[2] = TEXEL_FETCH(sTransformPalette, uv0, 0, ivec2(6, 0)); + transform.inv_m[3] = TEXEL_FETCH(sTransformPalette, uv0, 0, ivec2(7, 0)); + + return transform; +} + +// Return the intersection of the plane (set up by "normal" and "point") +// with the ray (set up by "ray_origin" and "ray_dir"), +// writing the resulting scaler into "t". +bool ray_plane(vec3 normal, vec3 pt, vec3 ray_origin, vec3 ray_dir, out float t) +{ + float denom = dot(normal, ray_dir); + if (abs(denom) > 1e-6) { + vec3 d = pt - ray_origin; + t = dot(d, normal) / denom; + return t >= 0.0; + } + + return false; +} + +// Apply the inverse transform "inv_transform" +// to the reference point "ref" in CSS space, +// producing a local point on a Transform plane, +// set by a base point "a" and a normal "n". +vec4 untransform(vec2 ref, vec3 n, vec3 a, mat4 inv_transform) { + vec3 p = vec3(ref, -10000.0); + vec3 d = vec3(0, 0, 1.0); + + float t = 0.0; + // get an intersection of the Transform plane with Z axis vector, + // originated from the "ref" point + ray_plane(n, a, p, d, t); + float z = p.z + d.z * t; // Z of the visible point on the Transform + + vec4 r = inv_transform * vec4(ref, z, 1.0); + return r; +} + +// Given a CSS space position, transform it back into the Transform space. +vec4 get_node_pos(vec2 pos, Transform transform) { + // get a point on the scroll node plane + vec4 ah = transform.m * vec4(0.0, 0.0, 0.0, 1.0); + vec3 a = ah.xyz / ah.w; + + // get the normal to the scroll node plane + vec3 n = transpose(mat3(transform.inv_m)) * vec3(0.0, 0.0, 1.0); + return untransform(pos, n, a, transform.inv_m); +} + +#endif //WR_VERTEX_SHADER + +#ifdef WR_FRAGMENT_SHADER + +// Assume transform bounds are set to a large scale to signal they are invalid. +bool has_valid_transform_bounds() { + return vTransformBounds.w < 1.0e15; +} + +float init_transform_fs(vec2 local_pos) { + // Ideally we want to track distances in screen space after transformation + // as signed distance calculations lose context about the direction vector + // to exit the geometry, merely remembering the minimum distance to the + // exit. However, we can't always sanely track distances in screen space + // due to perspective transforms, clipping, and other concerns, so we do + // this in local space. However, this causes problems tracking distances + // in local space when attempting to scale by a uniform AA range later in + // the presence of a transform which actually has non-uniform scaling. + // + // To work around this, we independently track the distances on the local + // space X and Y axes and then scale them by the independent AA ranges (as + // computed from fwidth derivatives) for the X and Y axes. This can break + // down at certain angles (45 degrees or close to it), but still gives a + // better approximation of screen-space distances in the presence of non- + // uniform scaling for other rotations. + // + // Get signed distance from local rect bounds. + vec2 d = signed_distance_rect_xy( + local_pos, + vTransformBounds.xy, + vTransformBounds.zw + ); + + // Find the appropriate distance to apply the AA smoothstep over. + vec2 aa_range = compute_aa_range_xy(local_pos); + + // Only apply AA to fragments outside the signed distance field. + return distance_aa_xy(aa_range, d); +} + +float init_transform_rough_fs(vec2 local_pos) { + return point_inside_rect( + local_pos, + vTransformBounds.xy, + vTransformBounds.zw + ); +} + +#endif //WR_FRAGMENT_SHADER |