diff options
Diffstat (limited to 'src/spritebatch.cpp')
| -rw-r--r-- | src/spritebatch.cpp | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/src/spritebatch.cpp b/src/spritebatch.cpp new file mode 100644 index 0000000..91e04ba --- /dev/null +++ b/src/spritebatch.cpp @@ -0,0 +1,185 @@ +#include "spritebatch.hpp"
+
+SpriteBatch::SpriteBatch(GeoShader theshader) : _vbo(0), _vao(0), shader(theshader)
+{
+ //shader = theshader;
+}
+
+SpriteBatch::~SpriteBatch()
+{
+
+}
+
+void SpriteBatch::init()
+{
+ createVertexArray();
+}
+
+
+void SpriteBatch::begin() {
+ //_sortType = sortType;
+ _renderBatches.clear();
+
+ // Makes _glpyhs.size() == 0, however it does not free internal memory.
+ // So when we later call emplace_back it doesn't need to internally call new.
+ _gfx.clear();
+}
+
+void SpriteBatch::end() {
+ // Set up all pointers for fast sorting
+ _gfxPtr.resize(_gfx.size());
+ for (int i = 0; i < _gfx.size(); i++) {
+ _gfxPtr[i] = &_gfx[i];
+ }
+
+ //sortGlyphs();
+ createRenderBatches();
+}
+
+void SpriteBatch::draw(const GraphicsData& gfxData) {
+ _gfx.emplace_back(gfxData);
+}
+
+void SpriteBatch::renderBatch() {
+
+ // Bind our VAO. This sets up the opengl state we need, including the
+ // vertex attribute pointers and it binds the VBO
+ glBindVertexArray(_vao);
+
+ for (int i = 0; i < _renderBatches.size(); i++) {
+ //glBindTexture(GL_TEXTURE_2D, _renderBatches[i].texture);
+
+ glDrawArrays(GL_POINTS, _renderBatches[i].offset, _renderBatches[i].numVertices);
+ }
+ glBindVertexArray(0);
+}
+
+void SpriteBatch::createRenderBatches() {
+ // This will store all the vertices that we need to upload
+ std::vector <float> vertices;
+ // Resize the buffer to the exact size we need so we can treat
+ // it like an array
+ vertices.resize(_gfxPtr.size() * 6);
+
+ if (_gfxPtr.empty()) {
+ return;
+ }
+
+ int offset = 0; // current offset
+ int cv = 0; // current vertex
+
+ //Add the first batch
+ _renderBatches.emplace_back(offset, 6);
+ vertices[cv++] = _gfxPtr[0]->x;
+ vertices[cv++] = _gfxPtr[0]->y;
+ vertices[cv++] = _gfxPtr[0]->r;
+ vertices[cv++] = _gfxPtr[0]->g;
+ vertices[cv++] = _gfxPtr[0]->b;
+ vertices[cv++] = _gfxPtr[0]->sides;
+
+ offset += 6;
+
+ //Add all the rest of the glyphs
+ //std::cout << "ptr size = " << _gfxPtr.size() << std::endl;
+ for (int cg = 1; cg < _gfxPtr.size(); cg++) {
+
+ // Check if this glyph can be part of the current batch
+ //if (_gfxPtr[cg]->texture != _gfxPtr[cg - 1]->texture) {
+ // Make a new batch
+ // _renderBatches.emplace_back(offset, 6);
+ //} else {
+ // If its part of the current batch, just increase numVertices
+ _renderBatches.back().numVertices += 6;
+ //}
+ vertices[cv++] = _gfxPtr[cg]->x;
+ vertices[cv++] = _gfxPtr[cg]->y;
+ vertices[cv++] = _gfxPtr[cg]->r;
+ vertices[cv++] = _gfxPtr[cg]->g;
+ vertices[cv++] = _gfxPtr[cg]->b;
+ vertices[cv++] = _gfxPtr[cg]->sides;
+
+ offset += 6;
+ }
+
+
+
+ // Bind our VBO
+ glBindBuffer(GL_ARRAY_BUFFER, _vbo);
+ // Orphan the buffer (for speed)
+ glBufferData(GL_ARRAY_BUFFER, vertices.size() * sizeof(float), nullptr, GL_DYNAMIC_DRAW);
+ // Upload the data
+ glBufferSubData(GL_ARRAY_BUFFER, 0, vertices.size() * sizeof(float), vertices.data());
+
+ // Unbind the VBO
+ glBindBuffer(GL_ARRAY_BUFFER, 0);
+
+}
+
+void SpriteBatch::createVertexArray() {
+
+ // Generate the VAO if it isn't already generated
+ if (_vao == 0) {
+ glGenVertexArrays(1, &_vao);
+ }
+
+ // Bind the VAO. All subsequent opengl calls will modify it's state.
+ glBindVertexArray(_vao);
+
+ //G enerate the VBO if it isn't already generated
+ if (_vbo == 0) {
+ glGenBuffers(1, &_vbo);
+ }
+ glBindBuffer(GL_ARRAY_BUFFER, _vbo);
+
+ //Tell opengl what attribute arrays we need
+ GLint posAttrib = glGetAttribLocation(shader.m_program, "pos");
+ glEnableVertexAttribArray(posAttrib);
+
+ GLint colAttrib = glGetAttribLocation(shader.m_program, "color");
+ glEnableVertexAttribArray(colAttrib);
+
+ GLint sidesAttrib = glGetAttribLocation(shader.m_program, "sides");
+ glEnableVertexAttribArray(sidesAttrib);
+
+ // glEnableVertexAttribArray(2);
+
+ //This is the position attribute pointer
+ glVertexAttribPointer(posAttrib, 2, GL_FLOAT, GL_FALSE,
+ 6 * sizeof(float), 0); //This is the color attribute pointer
+ glVertexAttribPointer(colAttrib, 3, GL_FLOAT, GL_FALSE,
+ 6 * sizeof(float), (void*) (2 * sizeof(float))); //This is the UV attribute pointer
+ glVertexAttribPointer(sidesAttrib, 1, GL_FLOAT, GL_FALSE,
+ 6 * sizeof(float), (void*) (5 * sizeof(float)));
+ glBindVertexArray(0);
+
+}
+
+/*
+void SpriteBatch::sortGlyphs() {
+
+ switch (_sortType) {
+ case GlyphSortType::BACK_TO_FRONT:
+ std::stable_sort(_glyphPointers.begin(), _glyphPointers.end(), compareBackToFront);
+ break;
+ case GlyphSortType::FRONT_TO_BACK:
+ std::stable_sort(_glyphPointers.begin(), _glyphPointers.end(), compareFrontToBack);
+ break;
+ case GlyphSortType::TEXTURE:
+ std::stable_sort(_glyphPointers.begin(), _glyphPointers.end(), compareTexture);
+ break;
+ }
+}
+bool SpriteBatch::compareFrontToBack(Glyph* a, Glyph* b) {
+ return (a->depth < b->depth);
+}
+
+bool SpriteBatch::compareBackToFront(Glyph* a, Glyph* b) {
+ return (a->depth > b->depth);
+}
+
+bool SpriteBatch::compareTexture(Glyph* a, Glyph* b) {
+ return (a->texture < b->texture);
+}
+
+}
+*/
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