Primitive done.

src/engine/display/primitive.c

@@ -1,38 +1,42 @@
 #include "primitive.h"
 
-primitive_t * primitiveCreate(int32_t verticeCount) {
+primitive_t * primitiveCreate(int32_t verticeCount, int32_t indiceCount) {
   primitive_t *primitive = malloc(sizeof(primitive_t));
 
   primitive->verticeCount = verticeCount;
+  primitive->indiceCount = indiceCount;
 
-  size_t sizeIndices = sizeof(uint32_t) * verticeCount;
+  // size_t sizeIndices = sizeof(uint32_t) * verticeCount;
   size_t sizePositions = sizeof(float) * verticeCount * PRIMITIVE_POSITIONS_PER_VERTICE;
   size_t sizeCoordinates = sizeof(float) * verticeCount * PRIMITIVE_COORDINATES_PER_VERTICE;
-
-  //Setup Vertex Array Object
-  glGenVertexArrays(1, &primitive->vertexArray);
-  glBindVertexArray(primitive->vertexArray);
+  size_t sizeIndices = sizeof(indice_t) * indiceCount;
 
   // Create some buffers, one for the vertex data, one for the indices
-  GLuint buffer[2];
-  glGenBuffers(2, &buffer);
+  GLuint *buffer = malloc(sizeof(GLuint) * 2);
+  glGenBuffers(2, buffer);
 
   primitive->vertexBuffer = buffer[0];
   primitive->indexBuffer = buffer[1];
+  free(buffer);
   
   //Buffer an empty set of data then buffer each component
   glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, primitive->indexBuffer);
-  glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeIndices, GL_DYNAMIC_DRAW);
+  glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeIndices, 0, GL_DYNAMIC_DRAW);
 
   glBindBuffer(GL_ARRAY_BUFFER, primitive->vertexBuffer);
   glBufferData(GL_ARRAY_BUFFER, sizePositions+sizeCoordinates, 0, GL_DYNAMIC_DRAW);
 
   // Setup the attrib pointers
-  glVertexAttribPointer(0, PRIMITIVE_POSITIONS_PER_VERTICE, GL_FLOAT, GL_FALSE, 0, (void *)0);
-  glVertexAttribPointer(1, PRIMITIVE_COORDINATES_PER_VERTICE, GL_FLOAT, GL_FALSE, 0, (void *)0);
+  glVertexAttribPointer(0, PRIMITIVE_POSITIONS_PER_VERTICE, GL_FLOAT,
+    GL_FALSE, 0, (void *)0
+  );
+  glVertexAttribPointer(1, PRIMITIVE_COORDINATES_PER_VERTICE, GL_FLOAT,
+    GL_FALSE, 0, (void *)0
+  );
   glEnableVertexAttribArray(0);
   glEnableVertexAttribArray(1);
 
+
   return primitive;
 }
 
@@ -60,15 +64,16 @@ void primitiveBufferVertices(primitive_t *primitive,
 
   // Now copy the positions and coordinates from the vertices into the buffer
   for(i = 0; i < count; i++) {
-    positions[i * PRIMITIVE_POSITIONS_PER_VERTICE] = vertices[i]->x;
-    positions[i * PRIMITIVE_POSITIONS_PER_VERTICE + 1] = vertices[i]->y;
-    positions[i * PRIMITIVE_POSITIONS_PER_VERTICE + 2] = vertices[i]->z;
+    positions[i * PRIMITIVE_POSITIONS_PER_VERTICE] = vertices[i].x;
+    positions[i * PRIMITIVE_POSITIONS_PER_VERTICE + 1] = vertices[i].y;
+    positions[i * PRIMITIVE_POSITIONS_PER_VERTICE + 2] = vertices[i].z;
 
-    coordinates[i * PRIMITIVE_COORDINATES_PER_VERTICE] = vertices[i]->u;
-    coordinates[i * PRIMITIVE_COORDINATES_PER_VERTICE + 1] = vertices[i]->v;
+    coordinates[i * PRIMITIVE_COORDINATES_PER_VERTICE] = vertices[i].u;
+    coordinates[i * PRIMITIVE_COORDINATES_PER_VERTICE + 1] = vertices[i].v;
   }
 
   // Buffer the data into the GPU
+  glBindBuffer(GL_ARRAY_BUFFER, primitive->vertexBuffer);
   glBufferSubData(GL_ARRAY_BUFFER, offsetPositions, lengthPositions, positions);
   glBufferSubData(GL_ARRAY_BUFFER, offsetCoordinates, lengthCoordinates, positions);
 
@@ -78,7 +83,28 @@ void primitiveBufferVertices(primitive_t *primitive,
 }
 
 void primitiveBufferIndices(primitive_t *primitive, 
-  int32_t position, int32_t count, int32_t *indices
+  int32_t position, int32_t count, indice_t *indices
 ) {
+  size_t length, offset;
+  offset = position * sizeof(indice_t);
+  length = count * sizeof(indice_t);
 
+  glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, primitive->indexBuffer);
+  glBufferSubData(GL_ELEMENT_ARRAY_BUFFER, offset, length, indices);
 }
+
+void primitiveDraw(primitive_t *primitive, int32_t start, int32_t count) {
+  glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, primitive->indexBuffer);
+  glBindBuffer(GL_ARRAY_BUFFER, primitive->vertexBuffer);
+  glDrawElements(GL_TRIANGLES, count, GL_UNSIGNED_INT, (void *)(
+    sizeof(indice_t)*start
+  ));
+}
+
+void primitiveDispose(primitive_t *primitive) {
+  glBindBuffer(GL_ARRAY_BUFFER, 0);
+  glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
+	glDeleteBuffers(1, &primitive->vertexBuffer);
+	glDeleteBuffers(1, &primitive->indexBuffer);
+  free(primitive);
+}

src/engine/display/primitive.h

@@ -1,33 +1,69 @@
 #pragma once
 #include <stdint.h>
 #include <glad/glad.h>
+#include <malloc.h>
 
 #define PRIMITIVE_POSITIONS_PER_VERTICE 3
 #define PRIMITIVE_COORDINATES_PER_VERTICE 2
 
+/** Structure containing information about a primitive */
 typedef struct {
   int32_t verticeCount;
+  int32_t indiceCount;
 
-  GLuint vertexArray;
   GLuint vertexBuffer;
   GLuint indexBuffer;
 } primitive_t;
 
+/** Structure containing vertice position information */
 typedef struct {
   float x, y, z;
   float u, v;
 } vertice_t;
 
-primitive_t * primitiveCreate(int32_t verticeCount);
+/** Indice that references a specific vertice */
+typedef unsigned int indice_t;
 
+/**
+ * Creates a new primitive.
+ * @param verticeCount How many vertices can the primitive hold.
+ * @param indiceCount How many indices can the primitive hold.
+ * @return The newly created primitive ready to be buffered to.
+ */
+primitive_t * primitiveCreate(int32_t verticeCount, int32_t indiceCount);
+
+/**
+ * Buffer Vertices to a primitive for use in rendering.
+ * @param primitive The primitive to buffer vertices into.
+ * @param position The position (index) to overwrite the vertices of.
+ * @param count The count of vertices to buffer.
+ * @param vertices Array of vertices to buffer into the primitive.
+ */
 void primitiveBufferVertices(primitive_t *primitive,
   int32_t position, int32_t count, vertice_t *vertices
 );
 
+/**
+ * Buffer Indices to a primitive for use in rendering.
+ * @param primitive The primitive to buffer indices into.
+ * @param position The position (index) to overwrite the indices of.
+ * @param count The count of indices to buffer.
+ * @param indices Array of indices to buffer into the primitive.
+ */
 void primitiveBufferIndices(primitive_t *primitive, 
-  int32_t position, int32_t count, int32_t *indices
+  int32_t position, int32_t count, indice_t *indices
 );
 
+/**
+ * Draw a primitive. Primitives are drawn by their indices.
+ * @param primitive Primitive to draw.
+ * @param start Start indice (index) to draw.
+ * @param count Count of indices to draw.
+ */
 void primitiveDraw(primitive_t *primitive, int32_t start, int32_t count);
 
+/**
+ * Cleanup a previously created primitive.
+ * @param primitive Primitive to cleanup.
+ */
 void primitiveDispose(primitive_t *primitive);

src/engine/display/render.c

@@ -7,6 +7,8 @@
 
 #include "render.h"
 
+primitive_t *primitive;
+
 render_t * renderInit(char *name) {
   // Initialize the renderer
   render_t *render = malloc(sizeof(render_t));
@@ -21,24 +23,35 @@ render_t * renderInit(char *name) {
   glDepthMask(GL_TRUE);
   glDepthFunc(GL_LEQUAL);
 
+  // Test
+  for(int i = 0; i < 100; i++) {
+    vertice_t *vertices = malloc(sizeof(vertice_t) * 4);
+    indice_t *indices = malloc(sizeof(indice_t) * 6);
+
+    vertices[0].x = -1, vertices[0].y = -1, vertices[0].z = 0;
+    vertices[1].x =  1, vertices[1].y = -1, vertices[1].z = 0;
+    vertices[2].x = -1, vertices[2].y =  1, vertices[2].z = 0;
+    vertices[3].x =  1, vertices[3].y =  1, vertices[3].z = 0;
+
+    indices[0] = (indice_t)0;
+    indices[1] = (indice_t)1;
+    indices[2] = (indice_t)2;
+    
+    indices[3] = (indice_t)1;
+    indices[4] = (indice_t)2;
+    indices[5] = (indice_t)3;
+
+    primitive = primitiveCreate(4, 6);
+    primitiveBufferVertices(primitive, 0, 4, vertices);
+    primitiveBufferIndices(primitive, 0, 6, indices);
+  }
+  
   return render;
 }
 
 void renderFrame(render_t *render) {
   glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-
-  float z = 0.0f;
-
-  glBegin(GL_TRIANGLES);
-    glColor3f(1, 0, 0);
-    glVertex3f(-1, -1, z);
-
-    glColor3f(0, 1, 0);
-    glVertex3f(0, 1, z);
-
-    glColor3f(0, 0, 1);
-    glVertex3f(1, -1, z);
-  glEnd();
+  primitiveDraw(primitive, 0, 6);
 }
 
 bool renderDispose(render_t *render) {

src/engine/display/render.h

@@ -13,6 +13,7 @@
 #include <malloc.h>
 #include <glad/glad.h>
 #include <cglm/call.h>
+#include "primitive.h"
 
 /**
  * Contains information about the current render state, can be used for querying