diff options
Diffstat (limited to 'drivers/gles3/shaders/canvas_sdf.glsl')
| -rw-r--r-- | drivers/gles3/shaders/canvas_sdf.glsl | 205 |
1 files changed, 205 insertions, 0 deletions
diff --git a/drivers/gles3/shaders/canvas_sdf.glsl b/drivers/gles3/shaders/canvas_sdf.glsl new file mode 100644 index 0000000000..424ec22457 --- /dev/null +++ b/drivers/gles3/shaders/canvas_sdf.glsl @@ -0,0 +1,205 @@ +/* clang-format off */ +#[modes] + +mode_load = #define MODE_LOAD +mode_load_shrink = #define MODE_LOAD_SHRINK +mode_process = #define MODE_PROCESS +mode_store = #define MODE_STORE +mode_store_shrink = #define MODE_STORE_SHRINK + +#[specializations] + +#[vertex] + +layout(location = 0) in vec2 vertex_attrib; + +/* clang-format on */ + +uniform ivec2 size; +uniform int stride; +uniform int shift; +uniform ivec2 base_size; + +void main() { + gl_Position = vec4(vertex_attrib, 1.0, 1.0); +} + +/* clang-format off */ +#[fragment] + +#define SDF_MAX_LENGTH 16384.0 + +#if defined(MODE_LOAD) || defined(MODE_LOAD_SHRINK) +uniform lowp sampler2D src_pixels;//texunit:0 +#else +uniform highp isampler2D src_process;//texunit:0 +#endif + +uniform ivec2 size; +uniform int stride; +uniform int shift; +uniform ivec2 base_size; + +#if defined(MODE_LOAD) || defined(MODE_LOAD_SHRINK) || defined(MODE_PROCESS) +layout(location = 0) out ivec4 distance_field; +#else +layout(location = 0) out vec4 distance_field; +#endif + +vec4 float_to_vec4(float p_float) { + highp vec4 comp = fract(p_float * vec4(255.0 * 255.0 * 255.0, 255.0 * 255.0, 255.0, 1.0)); + comp -= comp.xxyz * vec4(0.0, 1.0 / 255.0, 1.0 / 255.0, 1.0 / 255.0); + return comp; +} + +void main() { + ivec2 pos = ivec2(gl_FragCoord.xy); + +#ifdef MODE_LOAD + + bool solid = texelFetch(src_pixels, pos, 0).r > 0.5; + distance_field = solid ? ivec4(ivec2(-32767), 0, 0) : ivec4(ivec2(32767), 0, 0); +#endif + +#ifdef MODE_LOAD_SHRINK + + int s = 1 << shift; + ivec2 base = pos << shift; + ivec2 center = base + ivec2(shift); + + ivec2 rel = ivec2(32767); + float d = 1e20; + int found = 0; + int solid_found = 0; + for (int i = 0; i < s; i++) { + for (int j = 0; j < s; j++) { + ivec2 src_pos = base + ivec2(i, j); + if (any(greaterThanEqual(src_pos, base_size))) { + continue; + } + bool solid = texelFetch(src_pixels, src_pos, 0).r > 0.5; + if (solid) { + float dist = length(vec2(src_pos - center)); + if (dist < d) { + d = dist; + rel = src_pos; + } + solid_found++; + } + found++; + } + } + + if (solid_found == found) { + //mark solid only if all are solid + rel = ivec2(-32767); + } + + distance_field = ivec4(rel, 0, 0); +#endif + +#ifdef MODE_PROCESS + + ivec2 base = pos << shift; + ivec2 center = base + ivec2(shift); + + ivec2 rel = texelFetch(src_process, pos, 0).xy; + + bool solid = rel.x < 0; + + if (solid) { + rel = -rel - ivec2(1); + } + + if (center != rel) { + //only process if it does not point to itself + const int ofs_table_size = 8; + const ivec2 ofs_table[ofs_table_size] = ivec2[]( + ivec2(-1, -1), + ivec2(0, -1), + ivec2(+1, -1), + + ivec2(-1, 0), + ivec2(+1, 0), + + ivec2(-1, +1), + ivec2(0, +1), + ivec2(+1, +1)); + + float dist = length(vec2(rel - center)); + for (int i = 0; i < ofs_table_size; i++) { + ivec2 src_pos = pos + ofs_table[i] * stride; + if (any(lessThan(src_pos, ivec2(0))) || any(greaterThanEqual(src_pos, size))) { + continue; + } + ivec2 src_rel = texelFetch(src_process, src_pos, 0).xy; + bool src_solid = src_rel.x < 0; + if (src_solid) { + src_rel = -src_rel - ivec2(1); + } + + if (src_solid != solid) { + src_rel = ivec2(src_pos << shift); //point to itself if of different type + } + + float src_dist = length(vec2(src_rel - center)); + if (src_dist < dist) { + dist = src_dist; + rel = src_rel; + } + } + } + + if (solid) { + rel = -rel - ivec2(1); + } + + distance_field = ivec4(rel, 0, 0); +#endif + +#ifdef MODE_STORE + + ivec2 rel = texelFetch(src_process, pos, 0).xy; + + bool solid = rel.x < 0; + + if (solid) { + rel = -rel - ivec2(1); + } + + float d = length(vec2(rel - pos)); + + if (solid) { + d = -d; + } + + d /= SDF_MAX_LENGTH; + d = clamp(d, -1.0, 1.0); + distance_field = float_to_vec4(d*0.5+0.5); + +#endif + +#ifdef MODE_STORE_SHRINK + + ivec2 base = pos << shift; + ivec2 center = base + ivec2(shift); + + ivec2 rel = texelFetch(src_process, pos, 0).xy; + + bool solid = rel.x < 0; + + if (solid) { + rel = -rel - ivec2(1); + } + + float d = length(vec2(rel - center)); + + if (solid) { + d = -d; + } + d /= SDF_MAX_LENGTH; + d = clamp(d, -1.0, 1.0); + distance_field = float_to_vec4(d*0.5+0.5); + +#endif +} |