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-rw-r--r--src/mbgl/programs/gl/heatmap.cpp141
1 files changed, 141 insertions, 0 deletions
diff --git a/src/mbgl/programs/gl/heatmap.cpp b/src/mbgl/programs/gl/heatmap.cpp
new file mode 100644
index 0000000000..59f8ad9f69
--- /dev/null
+++ b/src/mbgl/programs/gl/heatmap.cpp
@@ -0,0 +1,141 @@
+// NOTE: DO NOT CHANGE THIS FILE. IT IS AUTOMATICALLY GENERATED.
+
+#include <mbgl/programs/heatmap_program.hpp>
+#include <mbgl/programs/gl/shader_source.hpp>
+#include <mbgl/gl/program.hpp>
+
+namespace mbgl {
+namespace gfx {
+
+template <>
+std::unique_ptr<Program<HeatmapProgram>>
+Context::createProgram<gl::Context>(const ProgramParameters& programParameters) {
+ return gl::Program<HeatmapProgram>::createProgram(
+ reinterpret_cast<gl::Context&>(*this), programParameters, "heatmap",
+ programs::gl::shaderSource() + 7983, programs::gl::shaderSource() + 9030);
+}
+
+} // namespace gfx
+} // namespace mbgl
+
+// Uncompressed source of heatmap.vertex.glsl:
+/*
+
+#ifndef HAS_UNIFORM_u_weight
+uniform lowp float a_weight_t;
+attribute highp vec2 a_weight;
+varying highp float weight;
+#else
+uniform highp float u_weight;
+#endif
+
+
+#ifndef HAS_UNIFORM_u_radius
+uniform lowp float a_radius_t;
+attribute mediump vec2 a_radius;
+#else
+uniform mediump float u_radius;
+#endif
+
+
+uniform mat4 u_matrix;
+uniform float u_extrude_scale;
+uniform float u_opacity;
+uniform float u_intensity;
+
+attribute vec2 a_pos;
+
+varying vec2 v_extrude;
+
+// Effective "0" in the kernel density texture to adjust the kernel size to;
+// this empirically chosen number minimizes artifacts on overlapping kernels
+// for typical heatmap cases (assuming clustered source)
+const highp float ZERO = 1.0 / 255.0 / 16.0;
+
+// Gaussian kernel coefficient: 1 / sqrt(2 * PI)
+#define GAUSS_COEF 0.3989422804014327
+
+void main(void) {
+
+#ifndef HAS_UNIFORM_u_weight
+ weight = unpack_mix_vec2(a_weight, a_weight_t);
+#else
+ highp float weight = u_weight;
+#endif
+
+
+#ifndef HAS_UNIFORM_u_radius
+ mediump float radius = unpack_mix_vec2(a_radius, a_radius_t);
+#else
+ mediump float radius = u_radius;
+#endif
+
+
+ // unencode the extrusion vector that we snuck into the a_pos vector
+ vec2 unscaled_extrude = vec2(mod(a_pos, 2.0) * 2.0 - 1.0);
+
+ // This 'extrude' comes in ranging from [-1, -1], to [1, 1]. We'll use
+ // it to produce the vertices of a square mesh framing the point feature
+ // we're adding to the kernel density texture. We'll also pass it as
+ // a varying, so that the fragment shader can determine the distance of
+ // each fragment from the point feature.
+ // Before we do so, we need to scale it up sufficiently so that the
+ // kernel falls effectively to zero at the edge of the mesh.
+ // That is, we want to know S such that
+ // weight * u_intensity * GAUSS_COEF * exp(-0.5 * 3.0^2 * S^2) == ZERO
+ // Which solves to:
+ // S = sqrt(-2.0 * log(ZERO / (weight * u_intensity * GAUSS_COEF))) / 3.0
+ float S = sqrt(-2.0 * log(ZERO / weight / u_intensity / GAUSS_COEF)) / 3.0;
+
+ // Pass the varying in units of radius
+ v_extrude = S * unscaled_extrude;
+
+ // Scale by radius and the zoom-based scale factor to produce actual
+ // mesh position
+ vec2 extrude = v_extrude * radius * u_extrude_scale;
+
+ // multiply a_pos by 0.5, since we had it * 2 in order to sneak
+ // in extrusion data
+ vec4 pos = vec4(floor(a_pos * 0.5) + extrude, 0, 1);
+
+ gl_Position = u_matrix * pos;
+}
+
+*/
+
+// Uncompressed source of heatmap.fragment.glsl:
+/*
+
+#ifndef HAS_UNIFORM_u_weight
+varying highp float weight;
+#else
+uniform highp float u_weight;
+#endif
+
+
+uniform highp float u_intensity;
+varying vec2 v_extrude;
+
+// Gaussian kernel coefficient: 1 / sqrt(2 * PI)
+#define GAUSS_COEF 0.3989422804014327
+
+void main() {
+
+#ifdef HAS_UNIFORM_u_weight
+ highp float weight = u_weight;
+#endif
+
+
+ // Kernel density estimation with a Gaussian kernel of size 5x5
+ float d = -0.5 * 3.0 * 3.0 * dot(v_extrude, v_extrude);
+ float val = weight * u_intensity * GAUSS_COEF * exp(d);
+
+ gl_FragColor = vec4(val, 1.0, 1.0, 1.0);
+
+#ifdef OVERDRAW_INSPECTOR
+ gl_FragColor = vec4(1.0);
+#endif
+}
+
+*/
+