CWindowClient::CWindowClient(CWindow &window)
: CAbstractWindowClient(window)
, m_quadObj(QUAD_TOPLEFT, QUAD_SIZE)
{
const glm::vec4 GREEN = { 0.15f, 0.4f, 0.15f, 1.f };
GetWindow().SetBackgroundColor(GREEN);
CheckOpenGLVersion();
SetupOpenGLState();
const std::string vertexShader = CFilesystemUtils::LoadFileAsString("res/copytexture.vert");
const std::string checkersShader = CFilesystemUtils::LoadFileAsString("res/checkers.frag");
const std::string pictureShader = CFilesystemUtils::LoadFileAsString("res/checkers-and-triangle.frag");
m_programCheckers.CompileShader(vertexShader, ShaderType::Vertex);
m_programCheckers.CompileShader(checkersShader, ShaderType::Fragment);
m_programCheckers.Link();
m_programPicture.CompileShader(vertexShader, ShaderType::Vertex);
m_programPicture.CompileShader(pictureShader, ShaderType::Fragment);
m_programPicture.Link();
m_programQueue = { &m_programPicture, &m_programCheckers };
}
void CWindow::OnWindowInit(const glm::ivec2 &size)
{
(void)size;
SetupOpenGLState();
}
bool FontRenderer::DrawText(const char* text, float x, float y, float scalex, float scaley) {
if (!_isInitialized) {
return false;
}
if (_glyphTexturesDirty) {
if (!CreateGlyphTextures()) {
return false;
}
}
SaveOpenGLState();
SetupOpenGLState();
glUseProgram(_fontProgram.Handle());
glActiveTexture(GL_TEXTURE0);
glUniform1i(_glyphTextureUniform, 0);
glUniform4fv(_glyphColorUniform, 1, _fontColor);
// Setup vertex format for rendering
glBindVertexArray(_vaoGlyphCoords);
glBindBuffer(GL_ARRAY_BUFFER, _vboGlyphCoords);
// Loop through characters in string.
float glyphPosx = x;
float glyphPosy = y;
for (const char* character = text; *character; character++) {
const Glyph* glyph = GetGlyph(*character);
glBindTexture(GL_TEXTURE_2D, glyph->texture);
// Calculate the vertex and texture coordinates.
const float posx = glyphPosx + glyph->left * scalex;
const float posy = -glyphPosy - glyph->top * scaley;
const float width = glyph->width * scalex;
const float height = glyph->rows * scaley;
// Upload coordinates to GPU.
GlyphVertex* vertices = (GlyphVertex*)glMapBuffer(GL_ARRAY_BUFFER, GL_WRITE_ONLY);
if (vertices != nullptr) {
vertices[0] = GlyphVertex(posx, -posy, 0.0f, 0.0f);
vertices[1] = GlyphVertex(posx + width, -posy, 1.0f, 0.0f);
vertices[2] = GlyphVertex(posx, -posy - height, 0.0f, 1.0f);
vertices[3] = GlyphVertex(posx + width, -posy - height, 1.0f, 1.0f);
glUnmapBuffer(GL_ARRAY_BUFFER);
}
// Draw the character on the screen.
glDrawArrays(GL_TRIANGLE_STRIP, 0, kNumVertices);
// Advance the cursor to the start of the next character.
glyphPosx += (glyph->advance_x >> 6) * scalex;
glyphPosy += (glyph->advance_y >> 6) * scaley;
}
glUseProgram(0);
glBindVertexArray(0);
glBindTexture(GL_TEXTURE_2D, 0);
RestorePriorOpenGLState();
return (GetGLErrorVerbose() == GL_NO_ERROR);
}
