Files
MapLibreParticleLab/test/api/custom_layer.test.cpp
Bart Louwers 2a8ebc4906 core: rename mbgl directories to mln (#4511)
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
2026-08-22 20:50:14 +02:00

118 lines
4.3 KiB
C++

#if MLN_RENDER_BACKEND_OPENGL
#include <mln/test/util.hpp>
#include <mln/gfx/headless_frontend.hpp>
#include <mln/style/layers/custom_layer.hpp>
#include <mln/gl/defines.hpp>
#include <mln/map/map.hpp>
#include <mln/map/map_options.hpp>
#include <mln/platform/gl_functions.hpp>
#include <mln/storage/resource_options.hpp>
#include <mln/style/layers/fill_layer.hpp>
#include <mln/style/style.hpp>
#include <mln/util/io.hpp>
#include <mln/util/mat4.hpp>
#include <mln/util/run_loop.hpp>
#include <memory>
using namespace mln;
using namespace mln::style;
using namespace mln::platform;
// Note that custom layers need to draw geometry with a z value of 1 to take
// advantage of depth-based fragment culling.
static const GLchar* vertexShaderSource = R"MBGL_SHADER(
attribute vec2 a_pos;
void main() {
gl_Position = vec4(a_pos, 1, 1);
}
)MBGL_SHADER";
static const GLchar* fragmentShaderSource = R"MBGL_SHADER(
void main() {
gl_FragColor = vec4(0, 0.5, 0, 0.5);
}
)MBGL_SHADER";
// Not using any mbgl-specific stuff (other than a basic error-checking macro)
// in the layer implementation because it is intended to reflect how someone
// using custom layers might actually write their own implementation.
class TestLayer : public mln::style::CustomLayerHost {
public:
void initialize(const mln::style::CustomLayerInitParameters&) override {
program = MBGL_CHECK_ERROR(glCreateProgram());
vertexShader = MBGL_CHECK_ERROR(glCreateShader(GL_VERTEX_SHADER));
fragmentShader = MBGL_CHECK_ERROR(glCreateShader(GL_FRAGMENT_SHADER));
MBGL_CHECK_ERROR(glShaderSource(vertexShader, 1, &vertexShaderSource, nullptr));
MBGL_CHECK_ERROR(glCompileShader(vertexShader));
MBGL_CHECK_ERROR(glAttachShader(program, vertexShader));
MBGL_CHECK_ERROR(glShaderSource(fragmentShader, 1, &fragmentShaderSource, nullptr));
MBGL_CHECK_ERROR(glCompileShader(fragmentShader));
MBGL_CHECK_ERROR(glAttachShader(program, fragmentShader));
MBGL_CHECK_ERROR(glLinkProgram(program));
a_pos = MBGL_CHECK_ERROR(glGetAttribLocation(program, "a_pos"));
GLfloat triangle[] = {0, 0.5, 0.5, -0.5, -0.5, -0.5};
MBGL_CHECK_ERROR(glGenBuffers(1, &buffer));
MBGL_CHECK_ERROR(glBindBuffer(GL_ARRAY_BUFFER, buffer));
MBGL_CHECK_ERROR(glBufferData(GL_ARRAY_BUFFER, 6 * sizeof(GLfloat), triangle, GL_STATIC_DRAW));
}
void render(const mln::style::CustomLayerRenderParameters&) override {
MBGL_CHECK_ERROR(glUseProgram(program));
MBGL_CHECK_ERROR(glBindBuffer(GL_ARRAY_BUFFER, buffer));
MBGL_CHECK_ERROR(glEnableVertexAttribArray(a_pos));
MBGL_CHECK_ERROR(glVertexAttribPointer(a_pos, 2, GL_FLOAT, GL_FALSE, 0, nullptr));
MBGL_CHECK_ERROR(glDrawArrays(GL_TRIANGLE_STRIP, 0, 3));
}
void contextLost() override {}
void deinitialize() override {
if (program) {
MBGL_CHECK_ERROR(glDeleteBuffers(1, &buffer));
MBGL_CHECK_ERROR(glDetachShader(program, vertexShader));
MBGL_CHECK_ERROR(glDetachShader(program, fragmentShader));
MBGL_CHECK_ERROR(glDeleteShader(vertexShader));
MBGL_CHECK_ERROR(glDeleteShader(fragmentShader));
MBGL_CHECK_ERROR(glDeleteProgram(program));
}
}
GLuint program = 0;
GLuint vertexShader = 0;
GLuint fragmentShader = 0;
GLuint buffer = 0;
GLuint a_pos = 0;
};
TEST(CustomLayer, Basic) {
if (gfx::Backend::GetType() != gfx::Backend::Type::OpenGL) {
return;
}
util::RunLoop loop;
HeadlessFrontend frontend{1};
Map map(frontend,
MapObserver::nullObserver(),
MapOptions().withMapMode(MapMode::Static).withSize(frontend.getSize()),
ResourceOptions().withCachePath(":memory:").withAssetPath("test/fixtures/api/assets"));
map.getStyle().loadJSON(util::read_file("test/fixtures/api/water.json"));
map.jumpTo(CameraOptions().withCenter(LatLng{37.8, -122.5}).withZoom(10.0));
map.getStyle().addLayer(std::make_unique<CustomLayer>("custom", std::make_unique<TestLayer>()));
auto layer = std::make_unique<FillLayer>("landcover", "mapbox");
layer->setSourceLayer("landcover");
layer->setFillColor(Color{1.0, 1.0, 0.0, 1.0});
map.getStyle().addLayer(std::move(layer));
test::checkImage("test/fixtures/custom_layer/basic", frontend.render(map).image, 0.0006, 0.1);
}
#endif