add textshader

include/llmr/renderer/painter.hpp

@@ -14,6 +14,7 @@
 #include <llmr/shader/linejoin_shader.hpp>
 #include <llmr/shader/point_shader.hpp>
 #include <llmr/shader/raster_shader.hpp>
+#include <llmr/shader/text_shader.hpp>
 
 namespace llmr {
 
@@ -84,6 +85,7 @@ private:
     std::unique_ptr<PatternShader> patternShader;
     std::unique_ptr<PointShader> pointShader;
     std::unique_ptr<RasterShader> rasterShader;
+    std::unique_ptr<TextShader> textShader;
 
     // Set up the stencil quad we're using to generate the stencil mask.
     VertexBuffer tileStencilBuffer = {

include/llmr/shader/text_shader.hpp

@@ -12,15 +12,66 @@ public:
     void bind(char *offset);
 
     void setColor(float r, float g, float b, float a);
-    void setColor(const std::array<float, 4>& color);
+    void setColor(const std::array<float, 4> &color);
+    void setBuffer(float buffer);
+    void setGamma(float gamma);
+    void setExmatrix(const std::array<float, 16> &exmatrix);
+    void setAngle(float angle);
+    void setZoom(float zoom);
+    void setFlip(float flip);
+    void setFadedist(float fadedist);
+    void setMinfadezoom(float minfadezoom);
+    void setMaxfadezoom(float maxfadezoom);
+    void setFadezoom(float fadezoom);
+    void setTexsize(const std::array<float, 2> &texsize);
 
 private:
     int32_t a_pos = -1;
+    int32_t a_offset = -1;
+    int32_t a_tex = -1;
+    int32_t a_angle = -1;
+    int32_t a_minzoom = -1;
+    int32_t a_maxzoom = -1;
+    int32_t a_rangeend = -1;
+    int32_t a_rangestart = -1;
+    int32_t a_labelminzoom = -1;
 
     std::array<float, 4> color = {{}};
     int32_t u_color = -1;
-};
 
+    float buffer = 0.0f;
+    int32_t u_buffer = -1;
+
+    float gamma = 0.0f;
+    int32_t u_gamma = -1;
+
+    std::array<float, 16> exmatrix = {{}};
+    int32_t u_exmatrix = -1;
+
+    float angle = 0.0f;
+    int32_t u_angle = -1;
+
+    float zoom = 0.0f;
+    int32_t u_zoom = -1;
+
+    float flip = 0.0f;
+    int32_t u_flip = -1;
+
+    float fadedist = 0.0f;
+    int32_t u_fadedist = -1;
+
+    float minfadezoom = 0.0f;
+    int32_t u_minfadezoom = -1;
+
+    float maxfadezoom = 0.0f;
+    int32_t u_maxfadezoom = -1;
+
+    float fadezoom = 0.0f;
+    int32_t u_fadezoom = -1;
+
+    std::array<float, 2> texsize = {{}};
+    int32_t u_texsize = -1;
+};
 }
 
 #endif

src/renderer/painter.cpp

@@ -38,6 +38,7 @@ void Painter::setup() {
     assert(linejoinShader);
     assert(patternShader);
     assert(rasterShader);
+    assert(textShader);
 
 
     // Blending
@@ -65,6 +66,7 @@ void Painter::setupShaders() {
     patternShader = std::make_unique<PatternShader>();
     pointShader = std::make_unique<PointShader>();
     rasterShader = std::make_unique<RasterShader>();
+    textShader = std::make_unique<TextShader>();
 }
 
 void Painter::resize(int width, int height) {
@@ -476,6 +478,8 @@ void Painter::renderPoint(PointBucket& bucket, const std::string& layer_name, co
 
 void Painter::renderText(TextBucket& bucket, const std::string& layer_name, const Tile::ID& id) {
     // noop
+    useProgram(textShader->program);
+    textShader->setMatrix(matrix);
 }
 
 void Painter::renderDebug(const TileData::Ptr& tile_data) {

src/shader/shaders.cpp

@@ -33,7 +33,7 @@ const shader_source llmr::shaders[SHADER_COUNT] = {
        "uniform sampler2D u_image;\nuniform float u_opacity;\n\nvarying vec2 v_pos;\n\nvoid main() {\n    gl_FragColor = texture2D(u_image, v_pos) * u_opacity;\n}\n",
    },
    {
-       "attribute vec2 a_pos;\n\nuniform mat4 u_matrix;\n\nvoid main() {\n    gl_Position = u_matrix * vec4(a_pos, 0, 1);\n}\n",
-       "uniform vec4 u_color;\n\nvoid main() {\n    gl_FragColor = u_color;\n}\n",
+       "attribute vec2 a_pos;\nattribute vec2 a_offset;\nattribute vec2 a_tex;\nattribute float a_angle;\nattribute float a_minzoom;\nattribute float a_maxzoom;\nattribute float a_rangeend;\nattribute float a_rangestart;\nattribute float a_labelminzoom;\n\n\n// posmatrix is for the vertex position, exmatrix is for rotating and projecting\n// the extrusion vector.\nuniform mat4 u_matrix;\nuniform mat4 u_exmatrix;\nuniform float u_angle;\nuniform float u_zoom;\nuniform float u_flip;\nuniform float u_fadedist;\nuniform float u_minfadezoom;\nuniform float u_maxfadezoom;\nuniform float u_fadezoom;\n\nuniform vec2 u_texsize;\n\nvarying vec2 v_tex;\nvarying float v_alpha;\n\nvoid main() {\n\n    float a_fadedist = 10.0;\n    float rev = 0.0;\n\n    // u_angle is angle of the map, -128..128 representing 0..2PI\n    // a_angle is angle of the label, 0..256 representing 0..2PI, where 0 is horizontal text\n    float rotated = mod(a_angle + u_angle, 256.0);\n    // if the label rotates with the map, and if the rotated label is upside down, hide it\n    if (u_flip > 0.0 && rotated >= 64.0 && rotated < 192.0) rev = 1.0;\n\n    // If the label should be invisible, we move the vertex outside\n    // of the view plane so that the triangle gets clipped. This makes it easier\n    // for us to create degenerate triangle strips.\n    // u_zoom is the current zoom level adjusted for the change in font size\n    float z = 2.0 - step(a_minzoom, u_zoom) - (1.0 - step(a_maxzoom, u_zoom)) + rev;\n\n    // fade out labels\n    float alpha = clamp((u_fadezoom - a_labelminzoom) / u_fadedist, 0.0, 1.0);\n\n    if (u_fadedist >= 0.0) {\n        v_alpha = alpha;\n    } else {\n        v_alpha = 1.0 - alpha;\n    }\n    if (u_maxfadezoom < a_labelminzoom) {\n        v_alpha = 0.0;\n    }\n    if (u_minfadezoom >= a_labelminzoom) {\n        v_alpha = 1.0;\n    }\n\n    // if label has been faded out, clip it\n    z += step(v_alpha, 0.0);\n\n    // all the angles are 0..256 representing 0..2PI\n    // hide if (angle >= a_rangeend && angle < rangestart)\n    z += step(a_rangeend, u_angle) * (1.0 - step(a_rangestart, u_angle));\n\n    gl_Position = u_matrix * vec4(a_pos, 0, 1) + u_exmatrix * vec4(a_offset / 64.0, z, 0);\n    v_tex = a_tex * 4.0 / u_texsize;\n}\n",
+       "uniform sampler2D u_texture;\nuniform vec4 u_color;\nuniform float u_buffer;\nuniform float u_gamma;\n\nvarying vec2 v_tex;\nvarying float v_alpha;\n\nvoid main() {\n    float dist = texture2D(u_texture, v_tex).a;\n    float alpha = smoothstep(u_buffer - u_gamma, u_buffer + u_gamma, dist) * v_alpha;\n    gl_FragColor = u_color * alpha;\n}\n",
    }
 };

src/shader/text.fragment.glsl

@@ -1,5 +1,13 @@
+uniform sampler2D u_texture;
 uniform vec4 u_color;
+uniform float u_buffer;
+uniform float u_gamma;
+
+varying vec2 v_tex;
+varying float v_alpha;
 
 void main() {
-    gl_FragColor = u_color;
+    float dist = texture2D(u_texture, v_tex).a;
+    float alpha = smoothstep(u_buffer - u_gamma, u_buffer + u_gamma, dist) * v_alpha;
+    gl_FragColor = u_color * alpha;
 }

src/shader/text.vertex.glsl

@@ -1,7 +1,70 @@
 attribute vec2 a_pos;
+attribute vec2 a_offset;
+attribute vec2 a_tex;
+attribute float a_angle;
+attribute float a_minzoom;
+attribute float a_maxzoom;
+attribute float a_rangeend;
+attribute float a_rangestart;
+attribute float a_labelminzoom;
 
+
+// posmatrix is for the vertex position, exmatrix is for rotating and projecting
+// the extrusion vector.
 uniform mat4 u_matrix;
+uniform mat4 u_exmatrix;
+uniform float u_angle;
+uniform float u_zoom;
+uniform float u_flip;
+uniform float u_fadedist;
+uniform float u_minfadezoom;
+uniform float u_maxfadezoom;
+uniform float u_fadezoom;
+
+uniform vec2 u_texsize;
+
+varying vec2 v_tex;
+varying float v_alpha;
 
 void main() {
-    gl_Position = u_matrix * vec4(a_pos, 0, 1);
+
+    float a_fadedist = 10.0;
+    float rev = 0.0;
+
+    // u_angle is angle of the map, -128..128 representing 0..2PI
+    // a_angle is angle of the label, 0..256 representing 0..2PI, where 0 is horizontal text
+    float rotated = mod(a_angle + u_angle, 256.0);
+    // if the label rotates with the map, and if the rotated label is upside down, hide it
+    if (u_flip > 0.0 && rotated >= 64.0 && rotated < 192.0) rev = 1.0;
+
+    // If the label should be invisible, we move the vertex outside
+    // of the view plane so that the triangle gets clipped. This makes it easier
+    // for us to create degenerate triangle strips.
+    // u_zoom is the current zoom level adjusted for the change in font size
+    float z = 2.0 - step(a_minzoom, u_zoom) - (1.0 - step(a_maxzoom, u_zoom)) + rev;
+
+    // fade out labels
+    float alpha = clamp((u_fadezoom - a_labelminzoom) / u_fadedist, 0.0, 1.0);
+
+    if (u_fadedist >= 0.0) {
+        v_alpha = alpha;
+    } else {
+        v_alpha = 1.0 - alpha;
+    }
+    if (u_maxfadezoom < a_labelminzoom) {
+        v_alpha = 0.0;
+    }
+    if (u_minfadezoom >= a_labelminzoom) {
+        v_alpha = 1.0;
+    }
+
+    // if label has been faded out, clip it
+    z += step(v_alpha, 0.0);
+
+    // all the angles are 0..256 representing 0..2PI
+    // hide if (angle >= a_rangeend && angle < rangestart)
+    z += step(a_rangeend, u_angle) * (1.0 - step(a_rangestart, u_angle));
+
+    gl_Position = u_matrix * vec4(a_pos, 0, 1) + u_exmatrix * vec4(a_offset / 64.0, z, 0);
+    v_tex = a_tex * 4.0 / u_texsize;
 }

src/shader/text_shader.cpp

@@ -17,19 +17,85 @@ TextShader::TextShader()
     }
 
     a_pos = glGetAttribLocation(program, "a_pos");
+    a_offset = glGetAttribLocation(program, "a_offset");
+    a_tex = glGetAttribLocation(program, "a_tex");
+    a_angle = glGetAttribLocation(program, "a_angle");
+    a_minzoom = glGetAttribLocation(program, "a_minzoom");
+    a_maxzoom = glGetAttribLocation(program, "a_maxzoom");
+    a_rangeend = glGetAttribLocation(program, "a_rangeend");
+    a_rangestart = glGetAttribLocation(program, "a_rangestart");
+    a_labelminzoom = glGetAttribLocation(program, "a_labelminzoom");
 
     u_matrix = glGetUniformLocation(program, "u_matrix");
     u_color = glGetUniformLocation(program, "u_color");
+    u_buffer = glGetUniformLocation(program, "u_buffer");
+    u_gamma = glGetUniformLocation(program, "u_gamma");
+    u_exmatrix = glGetUniformLocation(program, "u_exmatrix");
+    u_angle = glGetUniformLocation(program, "u_angle");
+    u_zoom = glGetUniformLocation(program, "u_zoom");
+    u_flip = glGetUniformLocation(program, "u_flip");
+    u_fadedist = glGetUniformLocation(program, "u_fadedist");
+    u_minfadezoom = glGetUniformLocation(program, "u_minfadezoom");
+    u_maxfadezoom = glGetUniformLocation(program, "u_maxfadezoom");
+    u_fadezoom = glGetUniformLocation(program, "u_fadezoom");
+    u_texsize = glGetUniformLocation(program, "u_texsize");
 
     // fprintf(stderr, "TextShader:\n");
     // fprintf(stderr, "    - a_pos: %d\n", a_pos);
-    // fprintf(stderr, "    - u_matrix: %d\n", u_matrix);
+    // fprintf(stderr, "    - a_offset: %d\n", a_offset);
+    // fprintf(stderr, "    - a_tex: %d\n", a_tex);
+    // fprintf(stderr, "    - a_angle: %d\n", a_angle);
+    // fprintf(stderr, "    - a_minzoom: %d\n", a_minzoom);
+    // fprintf(stderr, "    - a_maxzoom: %d\n", a_maxzoom);
+    // fprintf(stderr, "    - a_rangeend: %d\n", a_rangeend);
+    // fprintf(stderr, "    - a_rangestart: %d\n", a_rangestart);
+    // fprintf(stderr, "    - a_labelminzoom: %d\n", a_labelminzoom);
     // fprintf(stderr, "    - u_color: %d\n", u_color);
+    // fprintf(stderr, "    - u_buffer: %d\n", u_buffer);
+    // fprintf(stderr, "    - u_gamma: %d\n", u_gamma);
+    // fprintf(stderr, "    - u_exmatrix: %d\n", u_exmatrix);
+    // fprintf(stderr, "    - u_angle: %d\n", u_angle);
+    // fprintf(stderr, "    - u_zoom: %d\n", u_zoom);
+    // fprintf(stderr, "    - u_flip: %d\n", u_flip);
+    // fprintf(stderr, "    - u_fadedist: %d\n", u_fadedist);
+    // fprintf(stderr, "    - u_minfadezoom: %d\n", u_minfadezoom);
+    // fprintf(stderr, "    - u_maxfadezoom: %d\n", u_maxfadezoom);
+    // fprintf(stderr, "    - u_fadezoom: %d\n", u_fadezoom);
+    // fprintf(stderr, "    - u_texsize: %d\n", u_texsize);
 }
 
 void TextShader::bind(char *offset) {
     glEnableVertexAttribArray(a_pos);
-    glVertexAttribPointer(a_pos, 2, GL_SHORT, false, 0, offset);
+    glVertexAttribPointer(a_pos, 2, GL_SHORT, false, 16, offset + 0);
+
+    glEnableVertexAttribArray(a_offset);
+    glVertexAttribPointer(a_offset, 2, GL_SHORT, false, 16, offset + 4);
+
+    glEnableVertexAttribArray(a_tex);
+    glVertexAttribPointer(a_tex, 2, GL_UNSIGNED_BYTE, false, 16, offset + 8);
+
+    glEnableVertexAttribArray(a_labelminzoom);
+    glVertexAttribPointer(a_labelminzoom, 1, GL_UNSIGNED_BYTE, false, 16,
+                          offset + 10);
+
+    glEnableVertexAttribArray(a_minzoom);
+    glVertexAttribPointer(a_minzoom, 1, GL_UNSIGNED_BYTE, false, 16,
+                          offset + 11);
+
+    glEnableVertexAttribArray(a_maxzoom);
+    glVertexAttribPointer(a_maxzoom, 1, GL_UNSIGNED_BYTE, false, 16,
+                          offset + 12);
+
+    glEnableVertexAttribArray(a_angle);
+    glVertexAttribPointer(a_angle, 1, GL_UNSIGNED_BYTE, false, 16, offset + 13);
+
+    glEnableVertexAttribArray(a_rangeend);
+    glVertexAttribPointer(a_rangeend, 1, GL_UNSIGNED_BYTE, false, 16,
+                          offset + 14);
+
+    glEnableVertexAttribArray(a_rangestart);
+    glVertexAttribPointer(a_rangestart, 1, GL_UNSIGNED_BYTE, false, 16,
+                          offset + 15);
 }
 
 void TextShader::setColor(const std::array<float, 4>& new_color) {
@@ -42,3 +108,80 @@ void TextShader::setColor(const std::array<float, 4>& new_color) {
 void TextShader::setColor(float r, float g, float b, float a) {
     setColor({{ r, g, b, a }});
 }
+
+void TextShader::setBuffer(float new_buffer) {
+    if (buffer != new_buffer) {
+        glUniform1f(u_buffer, new_buffer);
+        buffer = new_buffer;
+    }
+}
+
+void TextShader::setGamma(float new_gamma) {
+    if (gamma != new_gamma) {
+        glUniform1f(u_gamma, new_gamma);
+        gamma = new_gamma;
+    }
+}
+
+void TextShader::setExmatrix(const std::array<float, 16> &new_exmatrix) {
+    if (exmatrix != new_exmatrix) {
+        glUniformMatrix4fv(u_exmatrix, 1, GL_FALSE, new_exmatrix.data());
+        exmatrix = new_exmatrix;
+    }
+}
+
+void TextShader::setAngle(float new_angle) {
+    if (angle != new_angle) {
+        glUniform1f(u_angle, new_angle);
+        angle = new_angle;
+    }
+}
+
+void TextShader::setZoom(float new_zoom) {
+    if (zoom != new_zoom) {
+        glUniform1f(u_zoom, new_zoom);
+        zoom = new_zoom;
+    }
+}
+
+void TextShader::setFlip(float new_flip) {
+    if (flip != new_flip) {
+        glUniform1f(u_flip, new_flip);
+        flip = new_flip;
+    }
+}
+
+void TextShader::setFadedist(float new_fadedist) {
+    if (fadedist != new_fadedist) {
+        glUniform1f(u_fadedist, new_fadedist);
+        fadedist = new_fadedist;
+    }
+}
+
+void TextShader::setMinfadezoom(float new_minfadezoom) {
+    if (minfadezoom != new_minfadezoom) {
+        glUniform1f(u_minfadezoom, new_minfadezoom);
+        minfadezoom = new_minfadezoom;
+    }
+}
+
+void TextShader::setMaxfadezoom(float new_maxfadezoom) {
+    if (maxfadezoom != new_maxfadezoom) {
+        glUniform1f(u_maxfadezoom, new_maxfadezoom);
+        maxfadezoom = new_maxfadezoom;
+    }
+}
+
+void TextShader::setFadezoom(float new_fadezoom) {
+    if (fadezoom != new_fadezoom) {
+        glUniform1f(u_fadezoom, new_fadezoom);
+        fadezoom = new_fadezoom;
+    }
+}
+
+void TextShader::setTexsize(const std::array<float, 2> &new_texsize) {
+    if (texsize != new_texsize) {
+        glUniform2fv(u_texsize, 1, new_texsize.data());
+        texsize = new_texsize;
+    }
+}