graphics

commit b695b9d6b2b2da872f6cd0c1ec1ef36f0ac5b314
parent 32e699a54373d366ab7026bb854e34e8b0f6f97b
Author: Brian Swetland <swetland@frotz.net>
Date:   Sun, 15 Sep 2013 05:14:31 -0700

renderable: add xzgrid and fullscreenquad renderables

Diffstat:
A
common/Renderable.cc
 | 
107
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
M
common/Renderable.h
 | 
4
++++

2 files changed, 111 insertions(+), 0 deletions(-)
diff --git a/common/Renderable.cc b/common/Renderable.cc
@@ -0,0 +1,107 @@
+/* Copyright 2013 Brian Swetland <swetland@frotz.net>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "Renderable.h"
+
+class XZGrid : public Renderable {
+public:
+	XZGrid(float size, unsigned steps);
+	virtual void render(void);
+private:
+	VertexBuffer buf;
+	VertexAttributes attr;
+	unsigned count;
+};
+
+XZGrid::XZGrid(float size, unsigned steps) : Renderable() {
+	static VertexAttrDesc layout[] = {
+		{ 0, SRC_FLOAT, DST_FLOAT, 3, 0, 12, 0 },
+	};
+	count = (steps + 1) * 4;
+	VertexBuffer *vb = &buf;
+	float x, z;
+ 	float *varr = (float*) malloc(sizeof(float) * 3 * count);
+	float *vtx = varr;
+	float min = -(size / 2.0);
+	float max = (size / 2.0) + 0.0001;
+	float step = size / ((float) steps);
+	for (x = min; x < max; x += step) {
+		vtx[0] = x;
+		vtx[1] = 0.0;
+		vtx[2] = min;
+		vtx[3] = x;
+		vtx[4] = 0.0;
+		vtx[5] = max;
+		vtx += 6;
+	}
+	for (z = min; z < max; z += step) {
+		vtx[0] = min;
+		vtx[1] = 0.0;
+		vtx[2] = z;
+		vtx[3] = max;
+		vtx[4] = 0.0;
+		vtx[5] = z;
+		vtx += 6;
+	}
+	buf.load(varr, count * 3 * sizeof(float));
+	attr.init(layout, &vb, 1);
+}
+
+void XZGrid::render(void) {
+	attr.use();
+	glDrawArrays(GL_LINES, 0, count);
+}
+
+Renderable* Renderable::createXZgrid(float size, unsigned steps) {
+	return new XZGrid(size, steps);
+}
+
+static VertexAttrDesc fsq_layout[] = {
+	{ 0, SRC_FLOAT, DST_FLOAT,  2, 0, 16, 0 },
+	{ 1, SRC_FLOAT, DST_FLOAT,  2, 8, 16, 0 },
+};
+
+static float fsq_vertices[] = {     //  1,4    6
+	-1.0f,  1.0f,  0.0f,  1.0f, //   o  |  o
+	-1.0f, -1.0f,  0.0f,  0.0f, //      |
+	 1.0f, -1.0f,  1.0f,  0.0f, // -----|-----
+	-1.0f,  1.0f,  0.0f,  1.0f, //      |
+	 1.0f, -1.0f,  1.0f,  0.0f, //   o  |  o 
+	 1.0f,  1.0f,  1.0f,  1.0f, //   2    3,5
+};
+
+class FSQuad : public Renderable {
+public:
+	FSQuad();
+	virtual void render(void);
+private:
+	VertexBuffer vbuf;
+	VertexAttributes attr;
+};
+
+FSQuad::FSQuad() : Renderable() {
+	VertexBuffer *data[] = { &vbuf, &vbuf };
+	vbuf.load(fsq_vertices, sizeof(fsq_vertices));
+	attr.init(fsq_layout, data, 2);
+}
+
+void FSQuad::render(void) {
+	attr.use();
+	glDrawArrays(GL_TRIANGLES, 0, 6);
+}
+
+Renderable* Renderable::createFullscreenQuad(void) {
+	return new FSQuad();
+}
diff --git a/common/Renderable.h b/common/Renderable.h
@@ -22,6 +22,10 @@ class Renderable {
 public:
 	Renderable(void) {};
 	virtual void render(void) = 0;
+
+	static Renderable* createXZgrid(float size, unsigned steps);
+	static Renderable* createFullscreenQuad(void);
+
 private:
 	DISALLOW_COPY_AND_ASSIGN(Renderable);
 };