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Diffstat (limited to 'src/mbgl/shaders/line.cpp')
-rw-r--r-- | src/mbgl/shaders/line.cpp | 233 |
1 files changed, 233 insertions, 0 deletions
diff --git a/src/mbgl/shaders/line.cpp b/src/mbgl/shaders/line.cpp index 100b50d6f6..4b76d21483 100644 --- a/src/mbgl/shaders/line.cpp +++ b/src/mbgl/shaders/line.cpp @@ -10,5 +10,238 @@ const char* line::name = "line"; const char* line::vertexSource = source() + 41600; const char* line::fragmentSource = source() + 46063; +// Uncompressed source of line.vertex.glsl: +/* + + +// the distance over which the line edge fades out. +// Retina devices need a smaller distance to avoid aliasing. +#define ANTIALIASING 1.0 / DEVICE_PIXEL_RATIO / 2.0 + +// floor(127 / 2) == 63.0 +// the maximum allowed miter limit is 2.0 at the moment. the extrude normal is +// stored in a byte (-128..127). we scale regular normals up to length 63, but +// there are also "special" normals that have a bigger length (of up to 126 in +// this case). +// #define scale 63.0 +#define scale 0.015873016 + +attribute vec4 a_pos_normal; +attribute vec4 a_data; + +uniform mat4 u_matrix; +uniform mediump float u_ratio; +uniform vec2 u_gl_units_to_pixels; + +varying vec2 v_normal; +varying vec2 v_width2; +varying float v_gamma_scale; +varying highp float v_linesofar; + + +#ifndef HAS_UNIFORM_u_color +uniform lowp float a_color_t; +attribute highp vec4 a_color; +varying highp vec4 color; +#else +uniform highp vec4 u_color; +#endif + + +#ifndef HAS_UNIFORM_u_blur +uniform lowp float a_blur_t; +attribute lowp vec2 a_blur; +varying lowp float blur; +#else +uniform lowp float u_blur; +#endif + + +#ifndef HAS_UNIFORM_u_opacity +uniform lowp float a_opacity_t; +attribute lowp vec2 a_opacity; +varying lowp float opacity; +#else +uniform lowp float u_opacity; +#endif + + +#ifndef HAS_UNIFORM_u_gapwidth +uniform lowp float a_gapwidth_t; +attribute mediump vec2 a_gapwidth; +#else +uniform mediump float u_gapwidth; +#endif + + +#ifndef HAS_UNIFORM_u_offset +uniform lowp float a_offset_t; +attribute lowp vec2 a_offset; +#else +uniform lowp float u_offset; +#endif + + +#ifndef HAS_UNIFORM_u_width +uniform lowp float a_width_t; +attribute mediump vec2 a_width; +#else +uniform mediump float u_width; +#endif + + +void main() { + +#ifndef HAS_UNIFORM_u_color + color = unpack_mix_color(a_color, a_color_t); +#else + highp vec4 color = u_color; +#endif + + +#ifndef HAS_UNIFORM_u_blur + blur = unpack_mix_vec2(a_blur, a_blur_t); +#else + lowp float blur = u_blur; +#endif + + +#ifndef HAS_UNIFORM_u_opacity + opacity = unpack_mix_vec2(a_opacity, a_opacity_t); +#else + lowp float opacity = u_opacity; +#endif + + +#ifndef HAS_UNIFORM_u_gapwidth + mediump float gapwidth = unpack_mix_vec2(a_gapwidth, a_gapwidth_t); +#else + mediump float gapwidth = u_gapwidth; +#endif + + +#ifndef HAS_UNIFORM_u_offset + lowp float offset = unpack_mix_vec2(a_offset, a_offset_t); +#else + lowp float offset = u_offset; +#endif + + +#ifndef HAS_UNIFORM_u_width + mediump float width = unpack_mix_vec2(a_width, a_width_t); +#else + mediump float width = u_width; +#endif + + + vec2 a_extrude = a_data.xy - 128.0; + float a_direction = mod(a_data.z, 4.0) - 1.0; + + v_linesofar = (floor(a_data.z / 4.0) + a_data.w * 64.0) * 2.0; + + vec2 pos = a_pos_normal.xy; + + // x is 1 if it's a round cap, 0 otherwise + // y is 1 if the normal points up, and -1 if it points down + mediump vec2 normal = a_pos_normal.zw; + v_normal = normal; + + // these transformations used to be applied in the JS and native code bases. + // moved them into the shader for clarity and simplicity. + gapwidth = gapwidth / 2.0; + float halfwidth = width / 2.0; + offset = -1.0 * offset; + + float inset = gapwidth + (gapwidth > 0.0 ? ANTIALIASING : 0.0); + float outset = gapwidth + halfwidth * (gapwidth > 0.0 ? 2.0 : 1.0) + (halfwidth == 0.0 ? 0.0 : ANTIALIASING); + + // Scale the extrusion vector down to a normal and then up by the line width + // of this vertex. + mediump vec2 dist = outset * a_extrude * scale; + + // Calculate the offset when drawing a line that is to the side of the actual line. + // We do this by creating a vector that points towards the extrude, but rotate + // it when we're drawing round end points (a_direction = -1 or 1) since their + // extrude vector points in another direction. + mediump float u = 0.5 * a_direction; + mediump float t = 1.0 - abs(u); + mediump vec2 offset2 = offset * a_extrude * scale * normal.y * mat2(t, -u, u, t); + + vec4 projected_extrude = u_matrix * vec4(dist / u_ratio, 0.0, 0.0); + gl_Position = u_matrix * vec4(pos + offset2 / u_ratio, 0.0, 1.0) + projected_extrude; + + // calculate how much the perspective view squishes or stretches the extrude + float extrude_length_without_perspective = length(dist); + float extrude_length_with_perspective = length(projected_extrude.xy / gl_Position.w * u_gl_units_to_pixels); + v_gamma_scale = extrude_length_without_perspective / extrude_length_with_perspective; + + v_width2 = vec2(outset, inset); +} + +*/ + +// Uncompressed source of line.fragment.glsl: +/* + +#ifndef HAS_UNIFORM_u_color +varying highp vec4 color; +#else +uniform highp vec4 u_color; +#endif + + +#ifndef HAS_UNIFORM_u_blur +varying lowp float blur; +#else +uniform lowp float u_blur; +#endif + + +#ifndef HAS_UNIFORM_u_opacity +varying lowp float opacity; +#else +uniform lowp float u_opacity; +#endif + + +varying vec2 v_width2; +varying vec2 v_normal; +varying float v_gamma_scale; + +void main() { + +#ifdef HAS_UNIFORM_u_color + highp vec4 color = u_color; +#endif + + +#ifdef HAS_UNIFORM_u_blur + lowp float blur = u_blur; +#endif + + +#ifdef HAS_UNIFORM_u_opacity + lowp float opacity = u_opacity; +#endif + + + // Calculate the distance of the pixel from the line in pixels. + float dist = length(v_normal) * v_width2.s; + + // Calculate the antialiasing fade factor. This is either when fading in + // the line in case of an offset line (v_width2.t) or when fading out + // (v_width2.s) + float blur2 = (blur + 1.0 / DEVICE_PIXEL_RATIO) * v_gamma_scale; + float alpha = clamp(min(dist - (v_width2.t - blur2), v_width2.s - dist) / blur2, 0.0, 1.0); + + gl_FragColor = color * (alpha * opacity); + +#ifdef OVERDRAW_INSPECTOR + gl_FragColor = vec4(1.0); +#endif +} + +*/ + } // namespace shaders } // namespace mbgl |