+
+AlphaSprite::AlphaSprite()
+: prog() {
+ prog.LoadShader(
+ GL_VERTEX_SHADER,
+ "#version 330 core\n"
+
+ "layout(location = 0) in vec3 vtx_position;\n"
+ "layout(location = 1) in vec2 vtx_texture;\n"
+
+ "uniform mat4 M;\n"
+ "uniform mat4 MV;\n"
+ "uniform mat4 MVP;\n"
+
+ "out vec2 frag_tex_uv;\n"
+
+ "void main() {\n"
+ "gl_Position = MVP * vec4(vtx_position, 1);\n"
+ "frag_tex_uv = vtx_texture;\n"
+ "}\n"
+ );
+ prog.LoadShader(
+ GL_FRAGMENT_SHADER,
+ "#version 330 core\n"
+
+ "in vec2 frag_tex_uv;\n"
+
+ "uniform sampler2D tex_sampler;\n"
+ "uniform vec4 fg_color;\n"
+ "uniform vec4 bg_color;\n"
+
+ "out vec4 color;\n"
+
+ "void main() {\n"
+ "vec4 tex_color = texture(tex_sampler, frag_tex_uv);\n"
+ "vec4 factor = mix(bg_color, fg_color, tex_color.a);\n"
+ "color = vec4((tex_color * factor).rgb, factor.a);\n"
+ "}\n"
+ );
+ prog.Link();
+ if (!prog.Linked()) {
+ prog.Log(std::cerr);
+ throw std::runtime_error("link program");
+ }
+ m_handle = prog.UniformLocation("M");
+ mv_handle = prog.UniformLocation("MV");
+ mvp_handle = prog.UniformLocation("MVP");
+ sampler_handle = prog.UniformLocation("tex_sampler");
+ fg_color_handle = prog.UniformLocation("fg_color");
+ bg_color_handle = prog.UniformLocation("bg_color");
+
+ vao.Bind();
+ vao.BindAttributes();
+ vao.EnableAttribute(0);
+ vao.EnableAttribute(1);
+ vao.AttributePointer<glm::vec3>(0, false, offsetof(Attributes, position));
+ vao.AttributePointer<glm::vec2>(1, false, offsetof(Attributes, texture));
+ vao.ReserveAttributes(4, GL_STATIC_DRAW);
+ {
+ auto attrib = vao.MapAttributes(GL_WRITE_ONLY);
+ attrib[0].position = glm::vec3(-0.5f, -0.5f, 0.0f);
+ attrib[0].texture = glm::vec2(0.0f, 0.0f);
+ attrib[1].position = glm::vec3(-0.5f, 0.5f, 0.0f);
+ attrib[1].texture = glm::vec2(0.0f, 1.0f);
+ attrib[2].position = glm::vec3( 0.5f, -0.5f, 0.0f);
+ attrib[2].texture = glm::vec2(1.0f, 0.0f);
+ attrib[3].position = glm::vec3( 0.5f, 0.5f, 0.0f);
+ attrib[3].texture = glm::vec2(1.0f, 1.0f);
+ }
+ vao.BindElements();
+ vao.ReserveElements(7, GL_STATIC_DRAW);
+ {
+ auto element = vao.MapElements(GL_WRITE_ONLY);
+ element[ 0] = 0;
+ element[ 1] = 1;
+ element[ 2] = 2;
+ element[ 3] = 3;
+ }
+ vao.Unbind();
+}
+
+AlphaSprite::~AlphaSprite() {
+}
+
+void AlphaSprite::Activate() noexcept {
+ prog.Use();
+ glEnable(GL_DEPTH_TEST);
+ glDepthFunc(GL_LESS);
+ glEnable(GL_CULL_FACE);
+ glEnable(GL_BLEND);
+ glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+}
+
+void AlphaSprite::SetM(const glm::mat4 &mm) noexcept {
+ m = mm;
+ mv = v * m;
+ mvp = p * mv;
+ prog.Uniform(m_handle, m);
+ prog.Uniform(mv_handle, mv);
+ prog.Uniform(mvp_handle, mvp);
+}
+
+void AlphaSprite::SetVP(const glm::mat4 &vv, const glm::mat4 &pp) noexcept {
+ v = vv;
+ p = pp;
+ mv = v * m;
+ mvp = p * mv;
+ prog.Uniform(mv_handle, mv);
+ prog.Uniform(mvp_handle, mvp);
+}
+
+void AlphaSprite::SetMVP(const glm::mat4 &mm, const glm::mat4 &vv, const glm::mat4 &pp) noexcept {
+ m = mm;
+ v = vv;
+ p = pp;
+ mv = v * m;
+ mvp = p * mv;
+ prog.Uniform(m_handle, m);
+ prog.Uniform(mv_handle, mv);
+ prog.Uniform(mvp_handle, mvp);
+}
+
+void AlphaSprite::SetTexture(Texture &tex) noexcept {
+ glActiveTexture(GL_TEXTURE0);
+ tex.Bind();
+ prog.Uniform(sampler_handle, GLint(0));
+}
+
+void AlphaSprite::SetFgColor(const glm::vec4 &color) noexcept {
+ prog.Uniform(fg_color_handle, color);
+}
+
+void AlphaSprite::SetBgColor(const glm::vec4 &color) noexcept {
+ prog.Uniform(bg_color_handle, color);
+}
+
+void AlphaSprite::DrawRect() const noexcept {
+ vao.Bind();
+ vao.DrawTriangleStrip(4);
+}
+
+
+Canvas::Canvas()
+: prog()
+, vao() {
+ prog.LoadShader(
+ GL_VERTEX_SHADER,
+ "#version 330 core\n"
+
+ "layout(location = 0) in vec2 vtx_position;\n"
+
+ "uniform mat4 P;\n"
+ "uniform float z;\n"
+
+ "void main() {\n"
+ // disamond rule adjust
+ //"vec3 position = vtx_position + vec3(0.5, 0.5, 0.0);\n"
+ "gl_Position = P * vec4(vtx_position, z, 1);\n"
+ "}\n"
+ );
+ prog.LoadShader(
+ GL_FRAGMENT_SHADER,
+ "#version 330 core\n"
+
+ "uniform vec4 c;\n"
+
+ "out vec4 color;\n"
+
+ "void main() {\n"
+ "color = c;\n"
+ "}\n"
+ );
+ prog.Link();
+ if (!prog.Linked()) {
+ prog.Log(std::cerr);
+ throw std::runtime_error("link program");
+ }
+ p_handle = prog.UniformLocation("P");
+ z_handle = prog.UniformLocation("z");
+ c_handle = prog.UniformLocation("c");
+
+ vao.Bind();
+ vao.BindAttributes();
+ vao.EnableAttribute(0);
+ vao.AttributePointer<glm::vec2>(0, false, offsetof(Attributes, position));
+ vao.ReserveAttributes(255, GL_DYNAMIC_DRAW);
+ vao.BindElements();
+ vao.ReserveElements(255, GL_DYNAMIC_DRAW);
+ vao.Unbind();
+}
+
+Canvas::~Canvas() {
+}
+
+void Canvas::Resize(float w, float h) noexcept {
+ prog.Uniform(p_handle, glm::ortho(0.0f, w, h, 0.0f, 1.0e4f, -1.0e4f));
+}
+
+void Canvas::ZIndex(float z) noexcept {
+ prog.Uniform(z_handle, -z);
+}
+
+void Canvas::SetColor(const glm::vec4 &color) noexcept {
+ prog.Uniform(c_handle, color);
+}
+
+void Canvas::Activate() noexcept {
+ prog.Use();
+ glEnable(GL_DEPTH_TEST);
+ glDepthFunc(GL_LESS);
+ glEnable(GL_CULL_FACE);
+ glEnable(GL_BLEND);
+ glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+}
+
+void Canvas::DrawLine(const glm::vec2 &p1, const glm::vec2 &p2, float width) {
+ glm::vec2 d = glm::normalize(p2 - p1) * (width * 0.5f);
+ glm::vec2 n = glm::vec2(d.y, -d.x);
+ vao.Bind();
+ vao.BindAttributes();
+ {
+ auto attr = vao.MapAttributes(GL_WRITE_ONLY);
+ attr[0].position = p1 - d + n;
+ attr[1].position = p1 - d - n;
+ attr[2].position = p2 + d + n;
+ attr[3].position = p2 + d - n;
+ }
+ vao.BindElements();
+ {
+ auto elem = vao.MapElements(GL_WRITE_ONLY);
+ elem[0] = 0;
+ elem[1] = 1;
+ elem[2] = 2;
+ elem[3] = 3;
+ }
+ vao.DrawTriangleStrip(4);
+ vao.Unbind();
+}
+
+void Canvas::DrawRect(const glm::vec2 &p1, const glm::vec2 &p2, float width) {
+ glm::vec2 min(std::min(p1.x, p2.x), std::min(p1.y, p2.y));
+ glm::vec2 max(std::max(p1.x, p2.x), std::max(p1.y, p2.y));
+ glm::vec2 dg1(min.x, max.y);
+ glm::vec2 dg2(max.x, min.y);
+ glm::vec2 d(width * 0.5f, width * 0.5f);
+ glm::vec2 n(d.y, -d.x);
+ vao.Bind();
+ vao.BindAttributes();
+ {
+ auto attr = vao.MapAttributes(GL_WRITE_ONLY);
+ attr[0].position = min + d;
+ attr[1].position = min - d;
+ attr[2].position = dg1 + n;
+ attr[3].position = dg1 - n;
+ attr[4].position = max - d;
+ attr[5].position = max + d;
+ attr[6].position = dg2 - n;
+ attr[7].position = dg2 + n;
+ }
+ vao.BindElements();
+ {
+ auto elem = vao.MapElements(GL_WRITE_ONLY);
+ elem[0] = 0;
+ elem[1] = 1;
+ elem[2] = 2;
+ elem[3] = 3;
+ elem[4] = 4;
+ elem[5] = 5;
+ elem[6] = 6;
+ elem[7] = 7;
+ elem[8] = 0;
+ elem[9] = 1;
+ }
+ vao.DrawTriangleStrip(10);
+ vao.Unbind();
+}
+
+void Canvas::FillRect(const glm::vec2 &p1, const glm::vec2 &p2) {
+ glm::vec2 min(std::min(p1.x, p2.x), std::min(p1.y, p2.y));
+ glm::vec2 max(std::max(p1.x, p2.x), std::max(p1.y, p2.y));
+ glm::vec2 dg1(min.x, max.y);
+ glm::vec2 dg2(max.x, min.y);
+ vao.Bind();
+ vao.BindAttributes();
+ {
+ auto attr = vao.MapAttributes(GL_WRITE_ONLY);
+ attr[0].position = min;
+ attr[1].position = dg1;
+ attr[2].position = dg2;
+ attr[3].position = max;
+ }
+ vao.BindElements();
+ {
+ auto elem = vao.MapElements(GL_WRITE_ONLY);
+ elem[0] = 0;
+ elem[1] = 1;
+ elem[2] = 2;
+ elem[3] = 3;
+ }
+ vao.DrawTriangleStrip(4);
+ vao.Unbind();
+}
+