linepattern in progress

9 files changed, 333 insertions, 13 deletions

diff --git a/include/mbgl/renderer/line_bucket.hpp b/include/mbgl/renderer/line_bucket.hpp
index c7e375a0a1..8babb734ed 100644
--- a/include/mbgl/renderer/line_bucket.hpp
+++ b/include/mbgl/renderer/line_bucket.hpp
@@ -17,10 +17,11 @@ class LineVertexBuffer;
 class TriangleElementsBuffer;
 class LineShader;
 class LinejoinShader;
+class LinepatternShader;
 struct pbf;
 
 class LineBucket : public Bucket {
-    typedef ElementGroup<1> triangle_group_type;
+    typedef ElementGroup<2> triangle_group_type;
     typedef ElementGroup<1> point_group_type;
 
 public:
@@ -38,6 +39,7 @@ public:
     bool hasPoints() const;
 
     void drawLines(LineShader& shader);
+    void drawLinePatterns(LinepatternShader& shader);
     void drawPoints(LinejoinShader& shader);
 
 public:
diff --git a/include/mbgl/renderer/painter.hpp b/include/mbgl/renderer/painter.hpp
index a8fe62b550..534323dd5d 100644
--- a/include/mbgl/renderer/painter.hpp
+++ b/include/mbgl/renderer/painter.hpp
@@ -14,6 +14,7 @@
 #include <mbgl/shader/pattern_shader.hpp>
 #include <mbgl/shader/line_shader.hpp>
 #include <mbgl/shader/linejoin_shader.hpp>
+#include <mbgl/shader/linepattern_shader.hpp>
 #include <mbgl/shader/icon_shader.hpp>
 #include <mbgl/shader/raster_shader.hpp>
 #include <mbgl/shader/text_shader.hpp>
@@ -169,6 +170,7 @@ public:
     std::unique_ptr<OutlineShader> outlineShader;
     std::unique_ptr<LineShader> lineShader;
     std::unique_ptr<LinejoinShader> linejoinShader;
+    std::unique_ptr<LinepatternShader> linepatternShader;
     std::unique_ptr<PatternShader> patternShader;
     std::unique_ptr<IconShader> iconShader;
     std::unique_ptr<RasterShader> rasterShader;
diff --git a/include/mbgl/shader/linepattern_shader.hpp b/include/mbgl/shader/linepattern_shader.hpp
new file mode 100644
index 0000000000..7d98b295a8
--- /dev/null
+++ b/include/mbgl/shader/linepattern_shader.hpp
@@ -0,0 +1,59 @@
+#ifndef MBGL_SHADER_SHADER_LINEPATTERN
+#define MBGL_SHADER_SHADER_LINEPATTERN
+
+#include <mbgl/shader/shader.hpp>
+
+namespace mbgl {
+
+class LinepatternShader : public Shader {
+public:
+    LinepatternShader();
+
+    void bind(char *offset);
+
+    void setExtrudeMatrix(const std::array<float, 16>& exmatrix);
+    void setLineWidth(const std::array<float, 2>& linewidth);
+    void setRatio(float ratio);
+    void setDebug(float debug);
+    void setPatternSize(const std::array<float, 2>& new_pattern_size);
+    void setPatternTopLeft(const std::array<float, 2>& new_pattern_tl);
+    void setPatternBottomRight(const std::array<float, 2>& new_pattern_br);
+    void setOffset(const std::array<float, 2>& offset);
+    void setGamma(float new_gamma);
+    void setFade(float new_fade);
+
+private:
+    int32_t a_pos = -1;
+    int32_t a_extrude = -1;
+    int32_t a_linesofar = -1;
+
+    std::array<float, 16> exmatrix = {{}};
+    int32_t u_exmatrix = -1;
+
+    std::array<float, 2> linewidth = {{}};
+    int32_t u_linewidth = -1;
+
+    float ratio = 0;
+    int32_t u_ratio = -1;
+
+    std::array<float, 2> pattern_size = {{}};
+    int32_t u_pattern_size = -1;
+
+    std::array<float, 2> pattern_tl = {{}};
+    int32_t u_pattern_tl = -1;
+
+    std::array<float, 2> pattern_br = {{}};
+    int32_t u_pattern_br = -1;
+
+    std::array<float, 2> offset = {{}};
+    int32_t u_offset = -1;
+
+    float gamma = 0.0f;
+    int32_t u_gamma = -1;
+
+    float fade = 0;
+    int32_t u_fade = -1;
+};
+}
+
+#endif
diff --git a/src/renderer/line_bucket.cpp b/src/renderer/line_bucket.cpp
index e089d7f61b..2e89a7c35d 100644
--- a/src/renderer/line_bucket.cpp
+++ b/src/renderer/line_bucket.cpp
@@ -374,6 +374,20 @@ void LineBucket::drawLines(LineShader& shader) {
     }
 }
 
+void LineBucket::drawLinePatterns(LinepatternShader& shader) {
+    char *vertex_index = BUFFER_OFFSET(vertex_start * vertexBuffer.itemSize);
+    char *elements_index = BUFFER_OFFSET(triangle_elements_start * triangleElementsBuffer.itemSize);
+    for (triangle_group_type& group : triangleGroups) {
+        if (!group.elements_length) {
+            continue;
+        }
+        group.array[1].bind(shader, vertexBuffer, triangleElementsBuffer, vertex_index);
+        glDrawElements(GL_TRIANGLES, group.elements_length * 3, GL_UNSIGNED_SHORT, elements_index);
+        vertex_index += group.vertex_length * vertexBuffer.itemSize;
+        elements_index += group.elements_length * triangleElementsBuffer.itemSize;
+    }
+}
+
 void LineBucket::drawPoints(LinejoinShader& shader) {
     char *vertex_index = BUFFER_OFFSET(vertex_start * vertexBuffer.itemSize);
     char *elements_index = BUFFER_OFFSET(point_elements_start * pointElementsBuffer.itemSize);
diff --git a/src/renderer/painter.cpp b/src/renderer/painter.cpp
index 2a3d45c9ed..938bd5bd84 100644
--- a/src/renderer/painter.cpp
+++ b/src/renderer/painter.cpp
@@ -41,6 +41,7 @@ void Painter::setup() {
     assert(outlineShader);
     assert(lineShader);
     assert(linejoinShader);
+    assert(linepatternShader);
     assert(patternShader);
     assert(rasterShader);
     assert(textShader);
@@ -70,6 +71,7 @@ void Painter::setupShaders() {
     if (!outlineShader) outlineShader = std::make_unique<OutlineShader>();
     if (!lineShader) lineShader = std::make_unique<LineShader>();
     if (!linejoinShader) linejoinShader = std::make_unique<LinejoinShader>();
+    if (!linepatternShader) linepatternShader = std::make_unique<LinepatternShader>();
     if (!patternShader) patternShader = std::make_unique<PatternShader>();
     if (!iconShader) iconShader = std::make_unique<IconShader>();
     if (!rasterShader) rasterShader = std::make_unique<RasterShader>();
diff --git a/src/renderer/painter_line.cpp b/src/renderer/painter_line.cpp
index ad0778fc0b..df2fb88193 100644
--- a/src/renderer/painter_line.cpp
+++ b/src/renderer/painter_line.cpp
@@ -1,6 +1,9 @@
 #include <mbgl/renderer/painter.hpp>
 #include <mbgl/renderer/line_bucket.hpp>
+#include <mbgl/style/style.hpp>
 #include <mbgl/style/style_layer.hpp>
+#include <mbgl/map/sprite.hpp>
+#include <mbgl/geometry/sprite_atlas.hpp>
 #include <mbgl/map/map.hpp>
 
 using namespace mbgl;
@@ -60,20 +63,50 @@ void Painter::renderLine(LineBucket& bucket, std::shared_ptr<StyleLayer> layer_d
         bucket.drawPoints(*linejoinShader);
     }
 
-    // var imagePos = properties.image && imageSprite.getPosition(properties.image);
-    bool imagePos = false;
-    if (imagePos) {
-        // var factor = 8 / Math.pow(2, painter.transform.zoom - params.z);
+    const std::shared_ptr<Sprite> &sprite = map.getSprite();
+    if (properties.image.size() && sprite) {
+        SpriteAtlas &spriteAtlas = *map.getSpriteAtlas();
+        Rect<uint16_t> imagePos = spriteAtlas.getImage(properties.image, *sprite);
+        
+        float factor = 8.0 / std::pow(2, map.getState().getIntegerZoom() - id.z);
+        
+        float fade = std::fmod(map.getState().getZoom(), 1.0);
 
-        // imageSprite.bind(gl, true);
+        std::array<float, 2> imageSize = {{
+            imagePos.w * factor,
+            imagePos.h * factor
+        }
+        };
 
-        // //factor = Math.pow(2, 4 - painter.transform.zoom + params.z);
-        // gl.switchShader(painter.linepatternShader, painter.translatedMatrix || painter.posMatrix, painter.extrudeMatrix);
-        // shader = painter.linepatternShader;
-        // glUniform2fv(painter.linepatternShader.u_pattern_size, [imagePos.size[0] * factor, imagePos.size[1] ]);
-        // glUniform2fv(painter.linepatternShader.u_pattern_tl, imagePos.tl);
-        // glUniform2fv(painter.linepatternShader.u_pattern_br, imagePos.br);
-        // glUniform1f(painter.linepatternShader.u_fade, painter.transform.z % 1.0);
+        std::array<float, 2> offset = {{
+            (float)std::fmod(id.x * 4096, imageSize[0]),
+            (float)std::fmod(id.y * 4096, imageSize[1])
+        }
+        };
+        useProgram(linepatternShader->program);
+        linepatternShader->setMatrix(vtxMatrix);
+        linepatternShader->setExtrudeMatrix(extrudeMatrix);
+        lineShader->setDashArray({{ dash_length, dash_gap }});
+        linepatternShader->setLineWidth({{ outset, inset }});
+        linepatternShader->setRatio(map.getState().getPixelRatio());
+        
+        linepatternShader->setPatternSize(imageSize);
+        linepatternShader->setPatternTopLeft({{
+            float(imagePos.x) / spriteAtlas.getWidth(),
+            float(imagePos.y) / spriteAtlas.getHeight(),
+        }});
+        linepatternShader->setPatternBottomRight({{
+            float(imagePos.x + imagePos.w) / spriteAtlas.getWidth(),
+            float(imagePos.y + imagePos.h) / spriteAtlas.getHeight(),
+        }});
+        linepatternShader->setOffset(offset);
+        linepatternShader->setGamma(map.getState().getPixelRatio());
+        linepatternShader->setFade(fade);
+        
+        spriteAtlas.bind(true);
+        glDepthRange(strata + strata_epsilon, 1.0f);  // may or may not matter
+        
+        bucket.drawLinePatterns(*linepatternShader);
 
     } else {
         useProgram(lineShader->program);
diff --git a/src/shader/linepattern.fragment.glsl b/src/shader/linepattern.fragment.glsl
new file mode 100644
index 0000000000..9d48adc5d4
--- /dev/null
+++ b/src/shader/linepattern.fragment.glsl
@@ -0,0 +1,34 @@
+uniform vec2 u_linewidth;
+uniform float u_gamma;
+uniform float u_fade;
+
+uniform vec2 u_pattern_size;
+uniform vec2 u_pattern_tl;
+uniform vec2 u_pattern_br;
+
+uniform sampler2D u_image;
+
+varying vec2 v_normal;
+varying float v_linesofar;
+
+void main() {
+    // Calculate the distance of the pixel from the line in pixels.
+    float dist = length(v_normal) * length(gl_PointCoord * 2.0 - 1.0);
+
+    // Calculate the antialiasing fade factor. This is either when fading in
+    // the line in case of an offset line (v_linewidth.t) or when fading out
+    // (v_linewidth.s)
+    float alpha = clamp(min(dist - (u_linewidth.t - 1.0), u_linewidth.s - dist) * u_gamma, 0.0, 1.0);
+
+    float x = mod(v_linesofar / u_pattern_size.x, 1.0);
+    float y = 0.5 + (v_normal.y * u_linewidth.s / u_pattern_size.y);
+    vec2 pos = mix(u_pattern_tl, u_pattern_br, vec2(x, y));
+    float x2 = mod(x * 2.0, 1.0);
+    vec2 pos2 = mix(u_pattern_tl, u_pattern_br, vec2(x2, y));
+
+    vec4 color = texture2D(u_image, pos) * (1.0 - u_fade) + u_fade * texture2D(u_image, pos2);
+
+    color.rgb *= color.a;
+
+    gl_FragColor = color * alpha;
+}
diff --git a/src/shader/linepattern.vertex.glsl b/src/shader/linepattern.vertex.glsl
new file mode 100644
index 0000000000..faf284c90a
--- /dev/null
+++ b/src/shader/linepattern.vertex.glsl
@@ -0,0 +1,53 @@
+// 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
+
+attribute vec2 a_pos;
+attribute vec2 a_extrude;
+attribute float a_linesofar;
+
+// posmatrix is for the vertex position, exmatrix is for rotating and projecting
+// the extrusion vector.
+uniform mat4 u_matrix;
+uniform mat4 u_exmatrix;
+
+// shared
+uniform float u_ratio;
+uniform vec2 u_linewidth;
+uniform vec4 u_color;
+
+varying vec2 v_normal;
+varying float v_linesofar;
+
+void main() {
+    // We store the texture normals in the most insignificant bit
+    // transform y so that 0 => -1 and 1 => 1
+    // In the texture normal, x is 0 if the normal points straight up/down and 1 if it's a round cap
+    // y is 1 if the normal points up, and -1 if it points down
+    vec2 normal = mod(a_pos, 2.0);
+    normal.y = sign(normal.y - 0.5);
+    v_normal = normal;
+
+    // Scale the extrusion vector down to a normal and then up by the line width
+    // of this vertex.
+    vec2 extrude = a_extrude / scale;
+    vec4 dist = vec4(u_linewidth.s * extrude, 0.0, 0.0);
+
+    // If the x coordinate is the maximum integer, we move the z coordinates out
+    // of the view plane so that the triangle gets clipped. This makes it easier
+    // for us to create degenerate triangle strips.
+    float z = step(32767.0, a_pos.x);
+
+    z += step(1.0, v_normal.y);
+
+    // Remove the texture normal bit of the position before scaling it with the
+    // model/view matrix. Add the extrusion vector *after* the model/view matrix
+    // because we're extruding the line in pixel space, regardless of the current
+    // tile's zoom level.
+
+    gl_Position = u_matrix * vec4(floor(a_pos / 2.0), 0.0, 1.0) + u_exmatrix * dist;
+    v_linesofar = a_linesofar; // * u_ratio;
+}
diff --git a/src/shader/linepattern_shader.cpp b/src/shader/linepattern_shader.cpp
new file mode 100644
index 0000000000..ec235f648e
--- /dev/null
+++ b/src/shader/linepattern_shader.cpp
@@ -0,0 +1,121 @@
+#include <mbgl/shader/linepattern_shader.hpp>
+#include <mbgl/shader/shaders.hpp>
+#include <mbgl/platform/gl.hpp>
+#include <iostream>
+
+#include <cstdio>
+
+using namespace mbgl;
+
+LinepatternShader::LinepatternShader()
+    : Shader(
+        "linepattern",
+         shaders[LINEPATTERN_SHADER].vertex,
+         shaders[LINEPATTERN_SHADER].fragment
+    ) {
+    if (!valid) {
+        fprintf(stderr, "invalid line pattern shader\n");
+        return;
+    }
+
+    a_pos = glGetAttribLocation(program, "a_pos");
+    a_extrude = glGetAttribLocation(program, "a_extrude");
+    a_linesofar = glGetAttribLocation(program, "a_linesofar");
+
+    u_matrix = glGetUniformLocation(program, "u_matrix");
+    u_exmatrix = glGetUniformLocation(program, "u_exmatrix");
+    u_linewidth = glGetUniformLocation(program, "u_linewidth");
+    u_ratio = glGetUniformLocation(program, "u_ratio");
+    u_pattern_size = glGetUniformLocation(program, "u_pattern_size");
+
+    u_pattern_tl = glGetUniformLocation(program, "u_pattern_tl");
+    u_pattern_br = glGetUniformLocation(program, "u_pattern_br");
+    u_offset = glGetUniformLocation(program, "u_offset");
+    u_gamma = glGetUniformLocation(program, "u_gamma");
+    u_fade = glGetUniformLocation(program, "u_fade");
+
+    //fprintf(stderr, "LinepatternShader:\n");
+    //fprintf(stderr, "    - u_matrix: %d\n", u_matrix);
+    //fprintf(stderr, "    - u_exmatrix: %d\n", u_exmatrix);
+    //fprintf(stderr, "    - u_linewidth: %d\n", u_linewidth);
+    //fprintf(stderr, "    - u_ratio: %d\n", u_ratio);
+    //fprintf(stderr, "    - u_pattern_size: %d\n", u_pattern_size);
+    //fprintf(stderr, "    - u_pattern_tl: %d\n", u_pattern_tl);
+    //fprintf(stderr, "    - u_pattern_br: %d\n", u_pattern_br);
+    //fprintf(stderr, "    - u_offset: %d\n", u_offset);
+    //fprintf(stderr, "    - u_gamma: %d\n", u_gamma);
+}
+
+void LinepatternShader::bind(char *offset) {
+    glEnableVertexAttribArray(a_pos);
+    glVertexAttribPointer(a_pos, 2, GL_SHORT, false, 8, offset + 0);
+
+    glEnableVertexAttribArray(a_extrude);
+    glVertexAttribPointer(a_extrude, 2, GL_BYTE, false, 8, offset + 4);
+
+    glEnableVertexAttribArray(a_linesofar);
+    glVertexAttribPointer(a_linesofar, 1, GL_SHORT, false, 8, offset + 6);
+}
+
+void LinepatternShader::setExtrudeMatrix(const std::array<float, 16>& new_exmatrix) {
+    if (exmatrix != new_exmatrix) {
+        glUniformMatrix4fv(u_exmatrix, 1, GL_FALSE, new_exmatrix.data());
+        exmatrix = new_exmatrix;
+    }
+}
+
+void LinepatternShader::setPatternSize(const std::array<float, 2>& new_pattern_size) {
+    if (pattern_size != new_pattern_size) {
+        glUniform2fv(u_pattern_size, 1, new_pattern_size.data());
+        pattern_size = new_pattern_size;
+    }
+}
+
+void LinepatternShader::setLineWidth(const std::array<float, 2>& new_linewidth) {
+    if (linewidth != new_linewidth) {
+        glUniform2fv(u_linewidth, 1, new_linewidth.data());
+        linewidth = new_linewidth;
+    }
+}
+
+void LinepatternShader::setRatio(float new_ratio) {
+    if (ratio != new_ratio) {
+        glUniform1f(u_ratio, new_ratio);
+        ratio = new_ratio;
+    }
+}
+
+void LinepatternShader::setPatternTopLeft(const std::array<float, 2>& new_pattern_tl) {
+    if (pattern_tl != new_pattern_tl) {
+        glUniform2fv(u_pattern_tl, 1, new_pattern_tl.data());
+        pattern_tl = new_pattern_tl;
+    }
+}
+
+void LinepatternShader::setPatternBottomRight(const std::array<float, 2>& new_pattern_br) {
+    if (pattern_br != new_pattern_br) {
+        glUniform2fv(u_pattern_br, 1, new_pattern_br.data());
+        pattern_br = new_pattern_br;
+    }
+}
+
+void LinepatternShader::setOffset(const std::array<float, 2>& new_offset) {
+    if (offset != new_offset) {
+        glUniform2fv(u_offset, 1, new_offset.data());
+        offset = new_offset;
+    }
+}
+
+void LinepatternShader::setGamma(float new_gamma) {
+    if (gamma != new_gamma) {
+        glUniform1f(u_gamma, new_gamma);
+        gamma = new_gamma;
+    }
+}
+
+void LinepatternShader::setFade(float new_fade) {
+    if (fade != new_fade) {
+        glUniform1f(u_fade, new_fade);
+        fade = new_fade;
+    }
+};